Category Archives: Principles of Eruvin

Eruvin 35 and 36 ספק דרבנן, ספק עירוב, and חזקה

Posted on by

On these daf, the Gemara deals with some of the most important principles in all of Halacha.

The Mishna on 35a records a dispute between Rabbi Meir and Rabbi Yossi regarding a case where it is uncertain whether the eruv techumin was valid during the critical period of twilight on Erev Shabbos.

Various examples are given:

1.       If the Eruv rolled outside his shabbos domain, and it is not clear if this happened before or after dark.

2.       If the Eruv was covered by landslide or burnt, and it unclear whether this happened before or after dark.

3.       If the Eruv consisted of Teruma, became impure, and it is unclear whether this happened before or after dark.

In such cases, Rabbi Meir and Rabbi Yehuda hold that he is treated like a “חמר גמל” (literally someone who is in charge of both a donkey and camel.)

As Rashi explains, the camel pulls from behind its leader, while the donkey pulls from  in front, making him remain stuck in place!

So also, it is unclear whether the Eruv is valid, allowing him  up to an extra 2000 amos in one direction, while limiting his movement  in the opposite direction, or whether it is invalid, keeping the status quo valid and allowing him 2000 amos in either direction.

As such, he is treated stringently and needs to avoid both areas of doubt, essentially making him “stuck” in the area of certainty between his house and where he placed the Eruv (roughly speaking, though probably really in the area where the two techumim overlap.)

In contrast, Rabbi Yossi and Rabbi Shimon rule that in case of doubt as to the validity of an eruv techumim, we are lenient and the eruv is kosher, allowing him to travel in a radius of 2000 amos from where he placed it.

It is unclear from their wording whether they mean that we treat the eruv as kosher out of doubt, thus also allowing him to walk anywhere within a 2000 amos radius of his house, or whether such an eruv is treated as if it is definitely kosher, thus preventing him from the later.

It is also unclear whether this debate is unique to a doubt regarding an eruv techumim, or applies to any case of doubt regarding a rabbinical law, as per the famous rule of ספק דרבנן לקולא (in case of doubt in a rabbinical matter, one may be lenient.)

The Gemara on 35b seems to take it for granted that this ruling is not unique to Eruvin, but applies to other areas of rabbinic law also, and questions Rabbi Meir’s ruling based on his lenient ruling in another case.

The case referred to is one where a person is impure  and goes down  to the mikva to immerse. himself.

Like in our case, there is some doubt as to whether his action was effective, for one of the following reasons:

1.       He is not sure if he actually immersed himself

2.       He is not sure if he immersed in a sufficient amount of water

3.       There were two mikvaos, one containing enough water and one which does not, and he is unsure which one he immersed in.

Rabbi Meir rules that if the person was impure on a biblical level, he is treated as impure, but if he was only impure on a rabbinical level, he is treated as if he is pure.

This seems to fit perfectly with the general halachik principle of ספק דאורייתא לחומרא  (in case of doubt in a biblical matter, we are stringent) and ספק דרבנן לקולא .

Rabbi Yossi, in contrast, holds that even if he was only rabbinically impure, he is still treated as impure out of doubt.

Here, it is Rabbi Meir who is lenient in the case of doubt, and Rabbi Yossi who is stringent.

Putting the issue of Rabbi Yossi’s apparent self-contradiction aside for a little, the Gemara focused first on Rabbi Meir, and answers that Rabbi Meir is of the view that the law forbidding one to leave one’s shabbos domain is actually biblical in nature.

As such, there is no inconsistency, and Rabbi Meir goes along with the general rule that ספק דרבנן לקולא.

On 36a, the Gemara turns to Rabbi Yosi and tries to explain the discrepancy in his ruling.

After various suggestions are given, the explanation of Rava is given.

Rava explains that although Rabbi Yossi indeed usually agrees that ספק דרבנן לקולא, in the case of the impure person, it is different because he started out with a חזקת אסור  (a forbidden status quo.)

The famous rule of following a person’s original status quo when there is doubt about his status (see Chullin 10a)  apparently overrides the rule of ספק דרבנן לקולא, or alternatively, redefines it as no longer subject to doubt, but as definitely impure.

There is tons more to discuss about the scope of these basic principles and how they relate to Eruvin and other situations- I wish to add that the continuation of the sugya seems to imply that Rabbi Yossi does not only limit the rule of ספק דרבנן לקולא to a case where there is no חזקת אסור working against it, but might even require a חזקת היתר  together with the doubt in order to be lenient.

This would be a huge novelty, with major ramifications, and would contradict much of what we know or assume about this rule- It would then come out that Rabbi Yossi is actually much stricter than Rabbi Meir (and perhaps the other opinions) regarding the scope of this leniency, contrary to what it seemed when we first learnt our Mishna!

Such is the beauty and complexity  of Gemara!

These posts are intended to raise issues and stimulate further research and discussion on contemporary topics related to the daf. They are not intended as psak halacha.

Eruvin 33 and 34 שבות בין השמשות and Eruv Techumim

Posted on by

Eruvin 33 and 34 שבות בין השמשות and Eruv Techumim

Our Masechta is starting to move deep into the detailed laws of עירוב תחומין, another type of Eruv that we have not focused on much till now.

In addition to the forbidden melacha of transporting things from one domain to another, there are also limitations on where a person himself may walk on Shabbos.

Though there is no prohibition on walking from one domain to another, there is a prohibition of walking outside one’s תחום של שבת, one’s shabbos domain.

This domain is measured 2000 amos (around or a little less than a km) from the place where one is or intends to base oneself for shabbos, as at nightfall before shabbos.

By default, it is measured from one’s own house, or if in a halachically defined city or enclosed private property, from the halachik boundaries of that city or private domain.

There is a debate on the next daf (Eruvin 35) as to whether the law of תחומין is biblical or rabbinical, but the 2000 Amah domain is very stringent, to the point that if someone leaves this area on shabbos, he might have to stay put within his own 4 amos for the rest of the shabbos!

Clearly, this has a major impact on people who wish to walk from one village to another on shabbos, sometimes even from one suburb to another, if the suburbs have significant open space between them (about 139 amos, which is not very much.)

In suburban neighborhoods with large open yards, this could even affect walking from one house to another, as each house might make up its own תחום!

This also applies to going for nature walks or hikes outside fenced resorts, or even within unfenced resorts.

To address this problem, Chazal allowed one who intends in advance to travel more than 2000 amos but less than 4000 amos from his shabbos base, to make an ערוב תחומין before shabbos.

By placing some food just under 2000 amos away from his base and intending to make that place his symbolic shabbos base, he would be permitted to go anywhere with a 2000 amah radius of where he put his food, rather than from his house.

The disadvantage of doing this, is that his house will now be on or at least closer to the boundaries of his new shabbos domain in the other direction, limiting his walking over the same shabbos in that direction- as such, his shabbos movements need to be planned very carefully.

One of the requirements for the food used for the Eruv is that the food has to be accessible from the place that one makes one’s new symbolic shabbos base.

The Mishna on 32b tells us that If one places one’s Eruv food on top of a tree, this might thus present a problem.

If one’s intended shabbos base is at the bottom of the tree, but the Eruv is more than 10 handbreadths high, and more than 4 handbreadths wide, the part of the tree above 10 handbreadths might form its own private domain.

This means that carrying his Eruv from the top to the bottom, assuming the tree is in a public domain, would be forbidden, and the Eruv would thus be invalid.

The mishna rules that if the Eruv is below 10 handbreadths, the Eruv is valid.

This seems to be despite the fact that an area between 3 and 10 handbreadths above a public domain might be considered a כרמלית (neither a private or public domain) and carrying the Eruv from there to one’s shabbos base at the bottom would thus be rabbinically forbidden.

In addition, there is a rabbinical prohibition against making use of a tree on shabbos, which extends to removing something from it.

As such, regardless of where it has been placed, it should be forbidden to remove it, and the Eruv should be invalid.

The Gemara solves the later problem (and according to Rashi, by implication the former too) by explaining that the validity of the Eruv is based on whether it may be carried to one’s shabbos base during the period of בית השמשות on shabbos eve.

Although its precise time and definition is also subject to much debate, this is generally viewed as the time between שקיעה (sunset) and צאת הכוכבים (the time the stars come out), and is also referred to as ספק חשכה ספק אינה חשיכה , a time when there is a doubt whether it is considered night yet or not.

This means that during this time, it is a doubt whether it is shabbos yet or not.

When it comes to biblical law, it goes without saying that one has to treat this time as if it is shabbos, due to the rule of ספק דאורייתא לחומרא .

Yet when it comes to rabbinical law, it is possible that Chazal followed the general rule of ספק דרבנן לקולא and did not treat that time as shabbos, thus making performing rabbinically prohibited activities (שבותים) permitted during that time.

It is also possible that seeing as Chazal were aware of the ambiguous nature of this period, but did not want to confuse us whether it is shabbos or not, they intentionally applied rabbinical prohibitions during this time as well, making it no longer a question of doubt.

The Gemara explains further that the author of our Mishna follows the view of Rebbe, who holds that Chazal did not impose their own rabbinical shabbos restrictions during this twilight period.

As such, at the crucial time of בין השמשות that determines the validity of the Eruv, the biblical prohibitions of removing something from a tree (or transferring it from a כרמלית to a רשות הרבים) does not apply, and the Eruv is valid!

On 33a, the Gemara brings an explicit Beraisa where Rebbe and the רבנן argue about an Eruv placed at a height of between 3 and 10 tefachim on a tree.

Rebbe is of the view that even though this area is a כרמלית and the Eruv may thus not be moved to the public domain at the base of the tree on shabbos itself, seeing as this rabbinical prohibition did not apply during בין השמשות, the Eruv is valid for the entire shabbos.

The Rabbis disagree, arguing that any Eruv that cannot be moved to one’s shabbos domain, is invalid- the Gemara seems to understand that while they agree that בין השמשות is the definitive time, they hold that these rabbinical prohibitions apply during בין השמשות as well.

This crucial debate is also found on 34b, regarding the same Mishna’s permission to place the eruv in a pit deeper than 10 tefachim, even though it too forms its own private domain.

The Gemara understands that this part of the mishna is referring to a case where one’s chosen shabbos base above the pit is a כרמלית , and that this once again reflects the lenient view of Rebbe that rabbinical restrictions of Shabbos do not apply בין השמשות.

It follows from all the above that according to Rebbe, though biblical prohibitions of shabbos apply from sunset on Erev shabbos, activities that are only forbidden rabbinically remain permitted until dark, which could be extremely useful for those well versed in shabbos laws (and very dangerous for those who are not.)

According to those Rabbis who disagree with him, both biblical and rabbinical prohibitions come into force the moment the sun sets on Friday. (I have assumed for purposes of this post that what we refer to today as sunset is the same as the talmudic concept of שקיעה, something which is in fact the subject of an entirely different discussion.

Given the rule that הלכה כרבי מחבריו, (the law usually follows Rebbe against his colleagues,) it seems likely that his lenient ruling here might actually be authoritative.

However, we need to examine closely at least one other major source on this subject.

This is an explicit Mishna (Shabbos 34a ) which states that during ספק חשכה ספק אינה חשיכה , the twilight period, certain actions forbidden on shabbos are forbidden, but others are permitted.

At first glance, this might seem to support the lenient view of Rebbe.

However, when examining the list, one finds some things that are only rabbinically forbidden on shabbos which one may also not do during twilight!

The list of forbidden things:

  1. separating tithes from ודאי (produce that has definitely or probably not been tithed)
  2. Immersing new vessels (טבילת כלים)
  3. Lighting candles

Whereas lighting candles is clearly a biblical prohibition, separating tithes and immersing vessels seem to be rabbinical prohibitions, yet they are still forbidden during twilight!

The list of permitted things:

  1. Separated tithes from דמאי (produce bought from an ignorant person who has probably but not definitely already separated tithes.)
  2. Making an Eruv
  3. Insulating hot food

The above 3 are all rabbinical requirements.

This Mishna seems to take a view between that of Rebbe and the Rabbis and permit certain rabbinically forbidden actions during twilight but forbid others.

This needs serious clarification, and there seem to be two main approaches to reconciling these Mishnayos amongst the commentators, but that is it for our daf!

These posts are intended to raise issues and stimulate further research and discussion on contemporary topics related to the daf. They are not intended as psak halacha.

Eruvin 24-25    The infamous קרפף, and Eruvin in resorts

Posted on by

We have seen that even though on a biblical level, an area surrounded by halachically acceptable partitions is considered a רשות היחיד , and one is  liable for transferring an object from it to a רשות הרבים, various concerns made Chazal impose other criteria in order to be able to carry with such an area.

In an area greater than a בית סאתיים , the area of the courtyard of the mishkan, which was 5000 square amos, inferior partitions made of only vertical or horizontal components, are not always sufficient.

In order to carry from one adjoining רשות היחיד  to another, an עירוב חצירות  is required, a requirement that forms the main subject of the next chapter.

We also see on our daf that an area that has not been מוקף לדירה (enclosed for the sake of habitation) might also not be considered a רשות היחיד .

Examples of this are enclosures used for growing vegetables. As the purpose of the enclosure is to protect the vegetables and not to mark an area for human habitation, the area has not been מוקף לדירה  and it is not treated with the leniencies of a רשות היחיד .

In addition, if such an area is contained within an area that has been enclosed for habitation and not fenced off, it can also nullify the partitions making it forbidden to carry within the entire area.

This restriction can have a major impact on large holiday resorts, particularly those in nature reserves, whose fences enclose a large area that usually includes many such areas that are not only not  enclosed for habitation but are also not even fit for habitation- these could  include natural bush and/or jungle, large ponds or lakes, and even areas inhabited by wild animals.

Not every such גינה  or קרפף  is subject to this stringency, however.

The Mishna on daf 23a told us that so long as a קרפף is less than our now famous בית סאתיים  measurement (5000 square amos,) one is permitted to carry within it.

Although there is some debate in the Mishna as to what criteria are needed even for such an area to be permitted, the Amoraim on daf 23b rule leniently like Rabbi Akiva that this permission is not dependant on any conditions.

On our daf 24a, Rav Nachman teaches us that a קרפף larger than this which was originally not closed for purposes of habitation may be validated for such purposes with a relatively simple fix:

One makes a gap in the boundaries of more than 10 טפחים, thus invalidating them, and recloses it with the correct purpose in mind.

While this could be a solution in resorts that agree to such an act, it might only work if there are no areas larger than a בית סאתיים  that remain physically unfit for habitation- this requires further discussion but could be a lingering constraint in the way of using the properties boundary fences as valid Eruv partitions.

Another issue commonly encountered is the issue of bodies of water on the properties, such as large ponds or lakes, larger than a בית סאתיים  which are unfit for human habitation, and might even contain crocodiles, hippos, or other dangerous animals.

Our Gemara makes it clear that although a body of fresh water which is fit for drinking  does not invalidate an area that has been enclosed for habitation (as Rashi points out, there is no greater habitation-related need than water!), this does not apply if the water is not fit for its normal use, which Rashi identifies as drinking.

As such bodies of water most often do not contain water that is fit for drinking, even in the absence of dangerous animals that make it their home, they might be problematic, depending on what the halachik definition of “fit for drinking” is and how the particular body of water fits that definition.

Another interesting question is whether there are any solutions for a  קרפף  that is slightly over the 5000 square amos threshhold.

On Daf 25a, the Gemara discusses whether one can reduce its area by partitioning part of it with trees and says that this is not sufficient .

It does allow one to build a platform large and high enough to be its own רשות היחיד  inside that area, thus taking it below the threshold.

Lots more to say and discuss about קרפפים  but it almost Shabbos, so Shabbat Shalom for now!

These posts are intended to raise issues and stimulate further research and discussion on contemporary topics related to the daf. They are not intended as psak halacha.

Eruvin 22-23 The sea as an Eruv revisited, Islands, and הוקף לדירה

Posted on by

In an earlier post, we discussed the debate around whether the sea may be used to close off a מבוי on one side.

On the one hand, the sea is deeper than the minimum 10 טפחים required, and at least at some point, the gradient is also sufficient, and we know from elsewhere (Shabbos 100a) that a pit filled with water is viewed as if it is empty as far as its depth is concerned.

On the other hand, there is a concern that the sea (or river) banks might accumulate שירטון (rocks and sand) to the point that the required gradient is on longer there, exposing an unfenced area between the sea and the מבוי.

We also saw that there is a dispute amongst the Rishonim as to whether we take this concern into account or not.

Today, we discuss a situation where an area is enclosed by the sea on all sides.

In such a case, there might be no concern of שירטון, as the entire area, including any banks or beaches that build up, are enclosed by the sea and thus could make up one large רשות היחיד (private domain.)

On the other hand, there might be additional reason for stringency seeing as the sea is not only being used for an area that is already enclosed by regular partitions on 2 or 3 sides, and thus probably already a רשות היחיד on a biblical level, but in place of partitions on all sides altogether!

The Gemara brings the radical ruling of Rabbi Yochanan that Eretz Yisrael is considered one large רשות היחיד at least on a biblical level (his precise words can better be paraphrased that one does not become liable to biblical punishment for carrying within it)

The Gemara first suggests that this might be because of the mountains and trenches that surround it, but notes that if this was sufficient, one could argue that Bavel (Mesopotamia) should also be one big רשות החיחד, seeing as it is enclosed by the 2 great rivers, the Euphrates and the Tigris.

The Gemara then goes further and argues that if a huge area surrounded by partitions is automatically considered one large רשות היחיד (as implied on Shabbos …) , one can argue that continents are all surrounded by the ocean, making them one large רשות היחיד as well, effectively rendering the biblical melacha of הוצאה null and void!

The truth is that the simple interpretation of Rabbi Yochanan’s statement seems absurd on its own, given that there are so many sources that imply that the melacha of הוצאה certainly applies on a biblical level in Eretz Yisrael, including Rabbi Yochanan’s own view that Yerushalayim would be a רשות הרבים if not for its doors being locked at night.

It is likely that the Gemara simply chose to ask further difficulties to highlight the further absurdity of this interpretation, rather than do so at this earlier stage (yet see Tosfos who deals with this issue.)

The Gemara thus concludes that Rabbi Yochanan is not referring to the whole of Eretz Yisrael, but only to the mountain passes in it.

It follows that there must be some limit regarding either the size or the nature of the area enclosed by partitions in order for it to be considered a רשות היחיד, and that neither Eretz Yisrael nor Bavel falls within whatever this limit is.

It is interesting that the Gemara did not mention the example of an island at all, which one could also have argued should be a רשות היחיד.

It could be that unlike a huge continent, the Gemara does not see this as such an absurd proposal, in which case we would need to find a cut-off point which defines the halachik parameters as to what is considered an island.

It is also possible, that the Gemara simply “went for the throat” as suggested above, choosing more extreme examples to highlight the absurdity of the idea, but an island would also clearly not qualify as a רשות היחיד .

In terms of the maximum size of a רשות הרבים, we have already seen that even a huge area can be closed off by complete partitions (as opposed to inferior partitions which have limitations at least on a rabbinical level) so basing the limit on size is far from straightforward.

Similarly, when it comes to purpose, we see here on daf 23b that large קרפפים are rabbinically disqualified from being considered a רשות היחיד, seeing as they were not closed off for the purpose of “living in,” but on a biblical level, this does not appear to be an issue either, and Rabbi Yochanan rules (Eruvin 67b) that one who throws from a רשות הרבים into such a קרפף is biblically liable- this forms the basis for the related sugya on our dapim (Eruvin 23b) as well.

The Rashba raises this issue and leaves it unresolved.

On the other hand, the Tosfos on our daf suggests that there is a difference between a partition made by people, which at least on a biblical level can enclose an area of any size, and a natural barrier, such as mountains or the sea, which is more limited even on a biblical level. The Meiri, though a little cryptic, seems to say a similar thing, differentiating between walls and “mountains and seas”

They too however, do not appear to define precisely what this limitation is- perhaps the main criteria would be whether the enclosed area is all ראוי לדירה (fit for human habitation,) which might exclude any islands which contain uninhabitable jungle, bush, desert or the like, but this needs further study.

The Ritva takes an entirely different approach, and quoting his Rebbe (probably Ramban,) claims that for any area to be considered a רשות הרבים even on a biblical level, one needs to רואה עצמו בתוך המחיצות (literally – see oneself inside the partitions.)

This phrase requires understanding, but the simple explanation seems to be that so long as one is able to see that he is inside a partitioned off area, (possibly even from a high vantage point, which could be possible even on very large properties) it is considered a רשות היחיד – if not, then it remains a רשות הרבים. (In truth, the Ritva points to his explanation of the sugya in sukkah 4b in the name of the Ramban which at face value does not appear to me to fit with this understanding, nor with the flow of the sugya here, but that’s for a more detailed study.)

This leaves open the possibility that according to this view, smaller islands would indeed be a רשות היחיד, at least on a biblical level, but means that larger properties without any line of site to the boundaries might not qualify, even if surrounded by man-made partitions!

These posts are intended to raise issues and stimulate further research and discussion on contemporary topics related to the daf. They are not intended as psak halacha.

Eruvin 20-21    The פסי ביראות  , public domain, and more on rabbinical laws

Posted on by

One of the main themes of this chapter is the special dispensation that Chazal gave to allow travelers to Yerushalayim for the chagim to draw water from wells for their animals.

The sides of these water-pits or wells were usually too steep for livestock to walk down to and drink, in contrast to people who were nimble enough to do so.

Seeing as the pit or well was surrounded by walls and more than 10 אמות  wide, it was defined as a private domain, and carrying the water from it to the public domain outside was thus forbidden.

To include an area around the well large enough for the animal to stand inside and drink in this private domain, Chazal made do with 4 double posts on each corner.

Each post was 6 handbreadths wide in each of its 2 perpendicular directions, forming a half square or widened L shape.

Although usually a private domain needs to be enclosed by proper partitions, with more closed space than open space, or at least a צורת הפתח, in the case of the special public mitzva of aliya laregel (going up to Yerushalayim for the festivals,) Chazal were lenient.

It seems clear from Daf 20a that this leniency is based on the fact that this method is already an acceptable form of enclosure  on a biblical level, otherwise Chazal would not be able to create such a method on their own to change the status of a רשות הרבים דאורייתא. This goes so far as to make someone who throws someone from a רשות הרבים into this enclosure liable to the biblical penalties prescribed for desecrating the Shabbos.

The implication of this is that the area around the wells is considered a fully-fledged public domain.

We have mentioned a few times already the view of Rashi (Eruvin 6a) that to be considered a public domain, a city needs to have at least 600000 people in it.

It is hard to imagine that the rural villages or city-outskirts where these wells were situated met this definition, which raises considerable difficulty with Rashi’s view.

It is possible that we are referring to the wells outside large population centers which were extremely crowded and busy, but even then, it seems a little far-fetched to imagine 600000 people frequenting them- Even during the busy period of aliya laregel, the population was unlikely to be concentrated in one such location at any time- further analysis is thus needed.

In the earlier dapim of the Masechta, we spent time  examining  the differences between biblical and rabbinical laws, and where they are found in the hierarchy.

We saw that on the one hand, we are usually stricter with biblical mitzvos, something we see all over through various halachik principles, but on the other hand, sometimes Chazal were more stringent with rabbinical laws in order to strengthen their authority.

On daf 21b, we see the incredible drasha of Rava, based on Koheles, that one should be even more careful with דברי סופרים  ( “the words of the scribes”- a term usually used for laws made after the time of Moshe, but itself requiring its own discussion) than with the words of the Torah.

This is because there is a range of positive and negative commandments in Torah, with a range of punishments, but when it comes to דברי סופרים , they are all treated equally severely to the point that העובר על דברי סופרים חייב מיתה  – one who goes against the words of the sofrim is liable to death.

Given that the maximum punishment carried out in court for one who transgresses rabbinical laws was generally מכת מרדות  (lashes for rebellion,) lower on the hierarchy of punishments than the 39 lashes given for biblical prohibitions under the correct strict conditions, this statement seems rather exaggerated, to put it mildly.

We see a similar phrase elsewhere, regarding  one who intentionally puts off saying the evening shema till after midnight, and the attack on Rabbi Tarfon by robbers while sitting to say shema was attributed to his failure to follow the authoritative ruling of Beis Hillel who hold that this is not necessary. )See also the Mishna  Sanhedrin 88b regarding Zakein Mamrei, and the Mishna in A.Z. 29b)

Furthermore, on our daf, we are told the incredible story of Rabbi Akiva who used this principle to justify his risking dehydration in captivity to use the little water he had for the rabbinical mitzva of נטילת ידים!

This extreme example might be the key to how to understand this entire concept- after all, we all know that one is only liable to given up one’s life for 3 of the worst biblical transgressions. We also know that one is often permitted to transgress rabbinical prohibitions even for curative purposes where danger to life is not involved.

This makes it virtually undisputable that this is not a normative halachik concept, but rather an idea, which might occasionally be applied halachically, but whose main purpose is to teach us the pivotal role of rabbinic law in Torah life. Specifically because of the many leniencies Chazal themselves applied to their decrees, it is necessary for them to remind us both in general and in certain specific cases how rabbinical law, routed in Torah law as it is (we will hopefully have future opportunity to discuss in what way this is the case ,) essentially stems  from the same divine authority.

Why Chazal choose to highlight this in certain cases specifically requires careful study, but we will leave that for another time.

Coming back to the issue we raised with Rashi’s view that a true public domain on a biblical level must have 600,000 people at a minimum, perhaps we can relook at the פסי ביראות  and why they need to be already validated as a partition on a biblical level.

Our assumption was that this must be because otherwise, chazal would not have the ability to treat them leniently in the case of the wells.

Perhaps, however, this assumption is not fully necessary?

There are times when Chazal do treat rabbinical laws as strictly or even more strictly than biblical ones. As we have seen above, and even times when the usual rule of אין גוזרין גזירה לגזירה   does not apply ( see גזירה שמט יעלה הים שירטון  as a possible example as well as recently on daf 20a “גזירה שמא יאמרו עירוב מועיל לבין הפסין” )

Perhaps, when it comes to something as novel as creating a new type of partition, Chazal were unwilling to do this even in an area which is only rabbinically treated like a public domain, out of concern that this would become a generally accepted type of partition even in cases they did not intend it to be relied on, maybe even in a real public domain?

This opens the possibility that the typical area around a well might indeed not be a true רשות הרבים  according to Rashi!

The problem is that Rashi himself seems to say explicitly that we are dealing with a true רשות הרבים  and true רשות היחיד-there are also numerous sugyos that imply that we are dealing with a true רשות הרבים  , including on our daf itself- I think that we might be able to work It out, but that’s is for today!

These posts are intended to raise issues and stimulate further research and discussion on contemporary topics related to the daf. They are not intended as psak halacha.

Eruvin 15-16 More on Eruv principles, dispute, and הלכה למשה מסיני

Posted on by

Our two daf contain pivotal sugyos regarding the laws of partitions and Eruvin.

One of them is a famous dispute between Abaya and Rava regarding a לחי העומד מאליו (a post that was already there prior to it being designated for use in closing off a מבוי.

The classic example is if a part of the one wall sticks out at a 90-degree angle to the wall, forming an effective post.

So long as he had in mind the day before that it should be used as a post for the Eruv, Abaya is of the view that it is acceptable.

On the other hand, Rava is of the view that seeing as it was not placed there specifically to serve as an Eruv pole, it is invalid.

After much back and forth, the Gemara brings a proof that Rav held like the lenient opinion of Abaya, which seems to be conclusive in allowing us to rule in his favor.

It is interesting that although we have a general rule that whenever Abaya and Rava disagree, we follow the ruling of Rava, the Gemara (Bava Metzia 22b ) gives an acronym יעל קגם for 6 cases where we follow Abaya, and Rashi identifies our case, לחי העומד מאליו as one of them.

We should note that at least in the case of our sugya, as well as the sugya quoted above, this is because the Gemara was able to find strong evidence in his favor.

We mentioned in our previous post that the Rambam (Mamrim 1/3) is of the view that things mentioned explicitly in the Torah or passed on orally to Moshe at Sinai are not subject to מחלוקת (debate,) and debates are only find regarding laws based on Chazal’s interpretations of the former through the rules of interpretation or rabbinical decrees and the like.

He also said (ibid 1/4) that even such debates were always settled eventually by the בית דין הגדול (great court or “Sanhedrin” of 71 ordained judges,) and once they were settled, there was no room for halachik debate.

In contrast, once the great court ceased to function, new debates remained essentially unsettled and each sage was free to follow and teach his own view to his students, who would typically follow their Rabbi- the default rule for undecided debates was to be stringent in biblical matters and lenient in rabbinical ones. (Mamrim 1/5)

In reality, this has not been the case, and in Amoraic Bavel where the much-weakened Sanhedrin back in Tiberius had little power, as well as after it ceased to function altogether, later Amoraim have come to conclusions regarding disputes which have thereafter also been regarded as binding.

There have even been rules of thumb formulated, such as following Rav over Shmuel, Rabbi Yochanan over Rav or Shmuel, and Rava over Abaya etc.

The Rambam himself (introduction to M.T.) explains the dictum of רבינא ורב אשי סוף הוראה (Bava Metzia 86a) as meaning that the later Amoraim, Ravina and Rav Ashi, who sealed the Talmud Bavli, essentially had the authority of בית דין הגדול for the last time in history, given that their rulings spread and were accepted by the Jewish people as a whole and all or most of its sages.

Although there is much to discuss and analyse here, it seems clear that a simple understanding of the earlier-quoted Rambam that makes authoritative dispute resolution entirely dependant on בית דין הגדול itself is not sufficient.

In another pivotal dispute, רב פפא, and רב הונא בריה דר’יהושע debate whether פרוץ כעומד (open area equivalent to closed area) is acceptable to consider a side as partitioned off or not.

The general rule is that when מחיצות (partitions) are used to close off a רשות היחיד, gaps of up to 10 אמות are permitted, and considered to be an acceptable פתח (opening) rather than a פירצה (gap)

However, there is an additional requirement recorded in the Mishna on 15b, that there may not be more open space than closed space (in the absence of a צורת הפתח in which case it is more complex.)

The Gemara on this Mishna opens with the above-mentioned debate regarding whether it is sufficient if the closed area is equal to the open area, or whether it needs to be MORE than the open area.

The Gemara seems to understand that the requirement that most of the partition not be open is a הלכה למשה מסיני (law given orally to Moshe at Sinai and passed on via tradition.)- (the precise term used here is “אגמריה רחמנא למשה” which seems pretty self-explanatory!)

It then understands the dispute to be a question of the nature of this הל”מ.

Was it a requirement not to allow most of the partition to be open, or was it a requirement requiring most of the partition to be closed?

Much debate follows onto daf 16 until in a major curveball, the halacha is resolved according to the lenient view, but this seems to be an explicit example of a dispute regarding something passed on explicitly to Moshe at Sinai, a counter-example to the Rambam’s hypothesis limiting such debate to matters involving the rules of interpretation or rabbinic decrees.

Once again, it seems that a simple explanation of the Rambam might not seem feasible and more analysis is required!

These posts are intended to raise issues and stimulate further research and discussion on contemporary topics related to the daf. They are not intended as psak halacha.

Eruvin 11 Eruv principles- צורת הפתח and מן הצד

Posted on by

One of the most important halachik constructs in the laws of Eruvin and מחיצות (partitions) in general is the idea of a צורת הפתח, the “form of an entrance.”

Although an area needs to be closed on 4 sides to be treated like a רשות היחיד (private domain) as far as permitting carrying there-in is concerned, this does not mean that all 4 sides need to be completely closed.

We have already seen in the first Mishna that the open fourth side of a מבוי can be marked symbolically with either a pole or a beam, so long as it is less than ten אמות wide.

The Mishna also taught us that if it has a צורת הפתח , the form of an entrance, it is fine even if it is more than 10 אמות wide.

It has been made clear that the “pole or beam” solution only works for a מבוי, with its strict criteria, but not for חצירות (courtyards) or other enclosures, which require either פסים (boards of at least 4 handbreadths wide) on one or more corners, or a צורת הפתח, which works even if the open fourth side is even wider than 10 אמות.

We see on today’s daf that a צורת הפתח can work to close openings of more than 10 אמות width even on the other mainly closed sides of an enclosure, and according to some opinions, can even serve as complete partitions on all 4 sides!

It is clear from the above that this is an extremely powerful tool, and today I would like to highlight a few of the rules relating to it, that are discussed on this daf.

A צורת הפתח is defined on our daf as “קנה מכאן וקנה מכאן וקנה על גביהן”- A reed on each side and a reed on top of them.

It seems from the wording that even though this is a more complex structure than simply a pole or a beam, a strong entity such as a pole or beam is not needed for this, and a reed or other symbolic item is sufficient, though of course this needs to be further clarified- our daf contains some discussion regarding the required properties of the horizontal and vertical components as well.

Whereas a gap of less than 10 אמות in a mainly solid partition is defined by default as a valid פתח (entrance) and does not invalidate the partition, a gap of more than is considered by default to be a פרצה (break) that needs to be “redefined” as an entrance by a physical structure baring some resemblance to the posts and lintel of an official entrance-way. This is achieved by the צורת הפתח under discussion.

One important requirement relating to a צורת הפתח is Rav Chisda’s ruling that the vertical component that goes from one side to the other needs to be above the two vertical components , not connected to its sides. Although there is some give and take on our daf regarding how universally accepted this limitation is as well as its scope, the conclusion does seem to be that this restriction certainly applies on as far as Shabbos law is concerned for openings of more than 10 אמות wide.

Whether it needs to physically touch the two vertical “reeds” or can be suspended directly above them by other structures (such as telephone or electricity wires and poles) is a different issue and subject to debate later on the daf.

Rav Chisda’s rule makes constructing an Eruv using the צורת הפתח model rather challenging, as balancing a reed or string on top of two other reeds, or even solid posts, is far harder than tying it to both sides.

Despite this, constructing a צורת הפתח , either permanently for city Eruvin or temporarily at a holiday resort, is usually more practical than constructing actual partitions, and is the preferred method most of the time.

One important question is whether the disqualification of “מן הצד” refers only to when the horizontal component of the צורת הפתח is attached at a lower level than the top of the vertical poles, but if it is tied to the sides right at the top of the vertical components, it is still considered to be “at the top.”

Some justification for this distinction could be that so long as the horizontal component is tied to the top of the vertical ones, the structure still resembles a regular entrance in some way, and the observer cannot easily tell the difference.

Rashi explains the phrase “מן הצד” as follows:

“שמתח הזמורה מזה לזה באמצעיתו ולא על ראשיהן”- he stretched the horizontal component (in this case a branch) from one vertical component to another in the middle of the verticals and not at their heads.”

Although admittedly ambiguous, this seems to indicate that at least according to Rashi, the main concern of מן הצד is if the horizontal component is tied somewhere between the top and bottom of the verticals (in the middle), and not right at the top, leaving the door open for permitting it to be tied to the “top” of their sides.

However, this does not seem to be the way the Rashba interpreted Rashi’s words:

“ומן הצד היינו שלא מתח הזמורה למעלה בראש הקונדיסין אלא באמצע הקונדסין ועל גבן היינו על גבן ממש”

“From the side means that he never stretched the branch above at the head of the poles but rather in the middle of the poles, and “on top of them” means precisely “on top.”

The emphasis of “precisely on top” seems to be clearly excluding the option of tying it to the top of the sides and insisting on it being literally “on top.”

The phrase “ in the middle” would refer to tying it anywhere along the height of the vertical component, as opposed to literally placing it “on top.”

When one looks at other Rishonim on this topic, one sees various other explanations of what מן הצד means, that could cause both leniencies and stringencies regarding when a צורת הפתח works, but for our purposes, I will just add that the Shulchan Aruch (O.C. 362/11) accepts Rashi’s basic understanding of מן הצד but does not discuss which understanding of Rashi is correct.

None other than the ט”ז himself, one of the most important commentaries on the Shulchan Aruch, understands Rashi in the more lenient way and allows the upper rope or string to be tied right at the top of the sides of the vertical reeds or poles. The Mishna Berura, however, notes that most Achronim disagree with him and accept the more stringent interpretation of Rashi, which we pointed out seems to be the way the Rashba understood him.

As such, while general practise is not to accept this leniency and to require the horizontal component to be literally on top or above the verticals, in difficult circumstances where this is not possible, the more lenient interpretation of Rashi accepted by the ט”ז might be acceptable, given that we are usually dealing with areas that are not considered a public domain on a biblical level.

These posts are intended to raise issues and stimulate further research and discussion on contemporary topics related to the daf. They are not intended as psak halacha.

Eruvin 9 and 10 Eruv principles- לבוד and פס ארבע

Posted on by

One of the most important rules regarding מחיצות (partitions) is the principle of לבוד.

The Gemara (Eruvin 4b) told us that this rule is הלכה למשה מסיני (see post on that daf.)

It states that any gap in partitions less than 3 טפחים in width is considered as if it is closed.

This has major ramifications both in the laws of Eruvin and of Sukkah.

It is necessary, however, to formulate exactly what the precise mechanism and scope of this rule is.

Let us suggest two possibilities for now:

  1. A gap that is less than 3 טפחים wide is not considered a gap at all, under any circumstances
  2. A gap that is less than 3 טפחים wide is still considered a gap, but it is the type of gap that is negligible enough to be ignored regarding certain מצוות.

If the first, objective definition is used, then it is irrelevant whether the gap’s effect is significant in practise or not, it simply does not count as a gap but is considered closed.

In contrast, according to the second formulation, there could be certain situations where such a gap is not negligible, and we do not disregard it.

In practise, it seems impossible to claim that such a gap has no noticeable effect on the partitions. It certainly lets in air from the outside, as well as insects and many smaller or medium sized animals that can get through the space. It also allows people to see inside, certainly no small thing.

As such, if the purpose of the partitions was meant to protect against the elements, keep small animals out, or create visual privacy, this rule seems highly illogical.

If, on the other hand, the purpose of the partitions is to demarcate the boundaries of a private domain, or keep larger animals out, then it makes sense that so long as the partitions are dominant and gaps are negligible, the partitions should still be valid.

At the bottom of the previous daf, the Gemara discussed a case where the beam is placed on two pegs protruding outwards from the public facing side of the existing walls of the מבוי.

As such, the beam is not on top of the מבוי, but the internal length of the beam is in contact with the walls.

Rav Chisda rules that the law depends on an earlier dispute we saw regarding the way in which the beam acts as a partition.

According to the opinion that normally permits one to carry underneath the beam, because we view the outside edge of the beam as the partition (as if it continues downwards to the ground,) this beam will be invalid, seeing as the outer edge is not in contact with the walls. Even though the beam might be only a טפח wide, and the gap between the outer edge and the walls should thus be viewed as “closed” due to the principle of לבוד, Rashi explains that seeing as this is not a real partition (but just a conceptual halachik construct) the leniency of לבוד does not apply.

According to the view that it is forbidden to carry underneath the beam because the inner edge of the beam forms the imaginary partition, in this case it will be permitted, seeing as the inner edge of the beam is in direct contact with the walls.

At this point, we already see that the rule of לבוד is not absolute but is limited to certain cases. After all, if it was absolute and a gap of less than 3 is never considered a gap at all, then it should apply even where the mechitzah is not real but only a halachik construct.

Rava holds that even according to the view that the imaginary partition is formed by the inner edge of the beam, this beam is not valid, seeing as it is not physically on top of the מבוי itself, something he requires.

Rav Ada bar Ahava objects on the basis of a beraisa that rules that if the beam is משוכה or תלויה less than 3 טפחים (or 4 טפחים acc רשב”ג) from the walls of the מבוי, it is sufficient due to the rule ofלבוד .

He understands that משוכה refers to when the beam is not directly over the מבוי but placed on pegs protruding outwards, as in the case we have been discussing.

He understands תלויה as referring to a case when the beam is suspended directly over the מבוי, but not directly over the walls of the מבוי- instead, it is supported by a reed placed in the middle of the opening and does reach the actual walls.

If the former assumption is correct, we see that there is no requirement for the beam to be physically on top of the מבוי, as claimed by Rava, and there also seems to be no limitation in the rule of לבוד that precludes it from being applied to another halachik construct such as an “imaginary” partition.

The Gemara answers that both the term משוכה and תלויה could be referring to a case when the beam is supported by a reed and doesn’t reach the wall but is still suspended directly over the מבוי.

The former term refers to a beam that reaches the walls of the מבוי on one side, whereas the later term refers to a beam that doesn’t not reach the walls on either side.

In both cases, the rule of לבוד makes it as if the beam reaches the walls.

However, in a case where the beam itself is not directly over the מבוי, לבוד does not help.

The Gemara explains that both these cases are needed, as we might have thought that the rule of לבוד can only be applied once, on one side, but not twice.

Once again, we see that the rule of לבוד is not a blanket rule, but has its limits- in this case, the Beraisa teaches us that both cases are within its limits, but if it did not have some limits, this would unnecessary.

Rav Ashi fails to see a significant distinction between applying the rule of לבוד on one side or on both sides, but says the Beraisa is referring to one case where the beam is both משוכה AND תלויה- thus removed both horizontally and vertically from the walls of the מבוי . In such a case, the rule of לבוד renders the horizonal gap ineffective and the rule of חבוט ( a different halachik construct whereby we view the edge of the beam as if it continues downwards till the walls) closes the vertical gap .

There is much to discuss regarding why the rule of לבוד isn’t used also for the vertical gap, and why the rule of חבוט is limited to only 3 טפחים, and Tosfos and other Rishonim go into this further, but for our purposes, the Gemara explains it was not a foregone conclusion that the rule of לבוד can be used in combination with another halachik construct like חבוט, and we needed the Beraisa to tell us that it can be.

We see from here also that the rule of לבוד was not seen as absolute by default but can have its limitations. To what extent the Beraisa has taught that that these limitations are not as great as we might have thought, or whether it has taught us that there are no limitations at all and that the rule of לבוד is indeed absolute, is still open for further analysis.

The rule of לבוד is applied once again at the bottom of 9b, in a discussion that flows over onto our new daf.

Here, we have been dealing with a case where a smaller courtyard opens on one side into a larger courtyard.

The walls that close the extra length of the outer courtyard can be seen from the larger courtyard, and the larger courtyard is thus not considered completely open on one side.

Seeing as the gap between the smaller and larger courtyard is less than 10 טפחים, it is considered as a valid entrance and the larger courtyard is considered sufficiently enclosed to carry inside it.

In contrast, the gap between the two courtyards forms the entire fourth side of the smaller courtyard, and as it is completely open, even a gap of less than 10 טפחים wide needs to be closed somehow.

Yet Rabbah bar Rav Huna has already concluded that נראה מבחוץ ושוה מבפנים (where the לחי used to close the fourth side of the מבוי can be seen from outside but not from inside) is permitted. Seeing as when viewed from the outside, the opening does not appear to take up the entire side, the smaller courtyard should also be fine as is.

The Gemara answers that we are dealing with a case where the sidewalls of the smaller courtyard extend into the larger courtyard, blocking the excess width of the shared wall from being seen from “outside” (the part of the larger courtyard that is opposite the smaller one.)

The Gemara asks that seeing as we are dealing with a larger courtyard that is no more than 1 Amah wider than the smaller one, there should be less than 3 טפחים between the side walls of the larger courtyard and those of the smaller one, and the rule of לבוד should effectively close this gap, making the whole area permitted.

It answers that we are dealing with a case where the smaller courtyard is not placed symmetrically in the middle of the larger one, but rather with a gap of 2 טפחים between its sidewalls and those of the larger courtyard on one side and 4 on the other.

Even though the rule of לבוד applies on the one side, it does not apply on the other, and according to the view of Rebbe who requires a courtyard completely open on one side to be marked on BOTH sides, the opening is still a problem.

This takes us into new territory entirely.

Until now, we have dealt with a מבוי that is closed on three sides but completely open on one side. מדרבנן it is forbidden to carry inside it until a post is placed on either side or a beam from one side to the other.

We already saw earlier that this does not apply to any area enclosed on 3 sides, but just to any area that has the very specific properties of a מבוי :

  1. At least 2 courtyards (with 2 houses each) opening to it
  2. Its length (2 closed sides) is greater than its width (one open and closed side.)

Today we see that a courtyard, which does not meet these qualifications, is treated more strictly, and according to Rebbe, needs to be partly closed on both ends of the open area, even if it is less than 10 אמות wide (if it is more, this might not even be sufficient.)

This has major ramifications for private front-yards and gardens, which we started discussing earlier in our post on daf 5, and I hope to be able to focus on this more as the discussion comes up in the Gemara.

Eruvin 8 The sea as an eruv

Posted on by

We have learnt that to be defined as a רשות היחיד (private domain,) an area needs to be surrounded by walls or partitions, at least 10 טפחים (handbreadths) high or deep.

We have also seen that מדאורייתא (biblically), מחיצות (partitions) on 3 sides is sufficient, but that מדרבנן (rabbinically), the fourth side needs to be marked or partially enclosed, depending on its width and status.

One of the most practical questions regarding the partitions used for the eruv concerns whether the sea or a river can be counted as a partition on one or more sides.

One the one hand, the water level could be very close to the level of the land, without the required 10 טפחים per 4 אמות drop (תל המתלקט) required for a partition.

On the other hand, given that water is not solid matter, and the ground underneath it often does drop at this gradient, perhaps the gradient should be measured by that of the solid ground which a person wading through the water would be walking down.

We have found explicitly (Shabbos 100a) that if a pit 10 טפחים deep is filled with water, even if the water reached the walls of the pit, it is still considered to be its own private domain.

This seems to show that a valley or depression filled with water could still be considered its own domain so long as its banks or the ground underneath it has the required gradient, serving as its partitions.

It follows logically that if these banks or slopes act as barriers for a different domain, they should also act as barriers for the domain that they separate this different domain from.

Our daf discusses the case of a מבוי that was surrounded on one side by a garbage pile and the other side by the sea.

There is a debate amongst the Rishonim whether these two sides were along the length of the מבוי or along the narrower widths of the מבוי, which could have its own ramifications, but we shall assume for now that 2 sides were closed correctly and 2 sides relied on the garbage heap and sea as partitions.

The Gemara related that רבי (Rabbi Yehuda haNasi) did not wish to either permit or forbid carrying in this מבוי.

He declined to forbid it seeing as there were valid partitions at the end of the day, but did not wish to permit it either, because of two concerns:

  1. The garbage might be removed leaving the one side without a partition.
  2. The sea could “bring up שירטון”- recede leaving washup-up stones and sand along the banks, thus destroying the natural partition.

The Gemara then asks what the opinion of the רבנן (the majority of sages) is, and two versions of events follow:

  1. רב יוסף בר אבדימי says that they forbid carrying in such a מבוי and Rav Nachman then rules like them.
  2. רב יוסף בר אבדימי says that they permit it, but Rav Nachman rules against them.

According to both versions brought by the Gemara, Rav Nachman forbids carrying in this מבוי , and given the lack of debate amongst the Amoraim, it is likely that this will be the halacha.

One question still open is whether the רבנן forbade carrying in this מבוי for both reasons thatרבי was concerned about, or only for one of them.

Perhaps their main concern was that that the garbage heap, which the Gemara concludes was privately owned, might be removed, a very likely event, but the less likely concern about the sea receding and leaving an unenclosed and relatively flat area of stones along its shore would not be a reason on its own to forbid it.

Another important question in this case is whether we are dealing with the sea or ocean, or with a river or lake.

Although the word ים is used, and this term usually refers to the seas specifically as opposed to rivers (see for example Brachos 9/Mishna 1 re ימים ונהרות )the concern of שירטון might apply to both, depending on precisely how we understand it.

Furthermore, most of the main Torah centers in Israel and possibly all of those in Bavel were not on the ocean.

Whereas the case that רבי dealt with could have been by the sea- major rivers are not present in Israel, the next case the Gemara brings seems almost certainly to have involved one of the main rivers of בבל, where most of its main centers were situated.

The Gemara describes how the Amora מרימר closed off the alleys of the city of Sura with nets, so as not to rely on the ים, for the same reason that רבי was initially concerned about.

As Sura was along the Euphrates River and certainly not on the coast, it seems that the term ים in this sugya certainly must also be referring to major rivers.

We see precedent for this in Tanach where the round pool in Shlomo’s palace was referred to as a ים (Melachim I 7/23) and was referred to by Chazal (Eruvin 14a) as the ים שעשה שלמה.

It is also clear from this case that מרימר was not only concerned about the garbage being removed but also about natural changes in the seashore or riverbank.

As such, the chapter should end here, and we should conclude that the sea or a river may not be used as the boundary of an eruv, period.

However, it is not quite as simple as that, thankfully.

Rabbeinu Chananel appears to have a different גירסא (version of the text) of the Gemara. In his girsa, the second version of the Gemara has Chachamim permitting the מבוי and Rav Nachman ruling leniently like them. It also narrates how אמימר closed the alleys of Sura with nets and was NOT concerned about שירטון .

This seems self- contradictory as if there was no concern for שירטון, why would nets be required, and many Rishonim reject this version out of hand (see for example Rashba on the daf)

This permissive view is given more teeth, however, by the Rambam, who rule (Shabbos 17/5 ) that the sea may serve as a partition, and we are not worried about שירטון.

The Meiri on our daf also rules leniently.

Perhaps what was meant by Rabbeinu Chananel’s version of the Gemara is that מרימר closed alleys that were not open to the sea with nets, and allowed the alleys that were open to the sea to be treated as closed even without nets, as he was not concerned about שירטון .

There is another major sugya in the second chapter of this masechta(Eruvin 22b) that is extremely relevant to this discussion, which I hope to discuss when we get there.

Practically speaking, the Shulchan Aruch (O.C. 363/29) rules leniently like the Rambam, whereas the Rema rules stringently like the Tur, Rashi’s version of the Gemara and other stringent poskim.

However, even those who allow the sea or river to be used as a partition could have rather strict conditions , among them:

  1. The gradient of the sea, river, or its banks has to be at least as steep as 10 handbreadths per 4 armlengths.
  2. The gap between the מבוי and the sea or river may not be more than the 10 handbreadth limit ( a wide beach between the street and the ocean could thus invalidate the entire partition.)
  3. The river cannot freeze solid during the winter (see Taz O.C. 363/20)

In addition, many Ashkenazi communities in Europe did use rivers as partitions for their Eruvin, and it thus seems that some of their authorities also held that the Gemara’s ban on using the sea or a river was not absolute, and depends on the circumstances.

As we have seen, this is a complex issue, and there is tons more to say, but one thing certain from this discussion is that anyone planning on relying on the sea or a river as an eruv boundary needs to know precisely what he is doing, or/and get guidance from someone who does!

These posts are intended to raise issues and stimulate further research and discussion on contemporary topics related to the daf. They are not intended as psak halacha.

Eruvin 6 An Eruv in a public domain

Posted on by

Until now, we have discussed how to close off the fourth side of a מבוי (alley) already closed on 3 sides, to permit carrying within the מבוי and to and from the מבוי and the adjoining courtyards.

We will see later that in addition to the pole or beam on the open side, one needs to make the actual eruv, known in this case as שתוף מבואות  (joining of alleys) by placing some food in one of the courtyards on behalf of all the inhabitants of the מבוי.

These laws are all based on the assumption that at a scriptural level, an area enclosed on 3 sides is already considered a private domain, and it is only a rabbinical requirement that the fourth side be marked or closed off in some way.

On today’s daf, we begin to address the more complex question of how to make an eruv in a real public domain, where carrying is a biblical prohibition.

The case discussed is a public thoroughfare with buildings flanking either side.

A Beraita is brought where the Tana Kama (first opinion) rules that one can make a צורת הפתח (a structure resembling an entrance, consisting of 2 poles on either side and a plank running from one side to the other on top) on one side, and the other side only requires pole or a beam (acc the version of the Rif and Rosh,) like a closed מבוי.

The Tana Chananya disagrees and says that the law in this case is subject to a dispute between Beis Hillel and Beis Shamai, and both are more stringent than the Tana Kama.

Beis Shamai holds that both ends need to be shut by doors which need to be locked as people enter or exit, a rather cumbersome process in a busy public place.

Beis Hillel are more lenient and require a door only on one side, making do with a pole or a beam on the other side, like a closed מבוי.

Even though Chananya’s view is substantially more stringent when it comes to a making an Eruv in a public domain, the Gemara is still unwilling to accept it due to 2 other statements of Chazal.

In the first, a Beraisa, Rabbi Yehuda opines that if someone has two houses on either side of a public thoroughfare , one may put either a pole or a beam on both of the open sides and carry from one house to another. This view is even more lenient than the Tana Kama in the previously Beraisa who requires at least a צורת הפתח on one side.

The Chachamim retorted that a public domain may simply not be closed off in such a lenient way.

In case one answers that the Chachamim did not mean to reject even Beis Hillel’s more stringent suggestion involving a door on one side, the Gemara brings an extremely stringent  view stated by Rabbah bar bar Hana in the name of the leading Amora, Rabbi Yochanan.

Rabbi Yochanan’s reported view is that even a walled city like Yerushalayim, would be considered a public domain on a biblical level, if its doors were not locked at night.

We are talking about a walled city enclosed on ALL sides, open only at the gates, yet Rabbi Yochanan holds that the gates required doors which were locked at night to convert it into a private domain (termed a חצר כל רבים, or public courtyard.)

We see from there that turning a public domain into a private domain is no simple matter, and even Beis Hillel’s requirement to have doors on one side are not sufficient for this- all sides have to be completely enclosed and even aligned gates on opposite sides of the city need to be completely closed with doors that are locked at night.

On the basis of this stringent ruling of Rabbi Yochanan, the Gemara reinterprets the first Beraisa to refer not to a real public domain, but to a מבוי that is open on both sides to a public domain, referred to as a מבוי מפולש לרשות הרבים.

Unlike the מבוי that is closed on 3 sides, this is treated more stringently, and the three opinions in the Beraisa refer to closing off its two open sides.

The Gemara then records a dispute between the leading first-generation Amoraim of Babylon, Rav and Shmuel, as to which opinion we follow for this open מבוי.

Rav rules like the Tana Kama and requires only a צורת הפתח on the one open side of the מבוי and a pole or beam on the other.

Shmuel is more stringent and requires doors on one side and a pole or beam on the other side, like Beis Hillel according to Chananya.

It follows that there are 3 different situations we have discussed so far:

1.       A real public domain, that satisfies all the criteria to be defined as such- making an eruv is almost impossible and requires doors in all openings that are locked at night.

2.       A מבוי that is open on two sides to the public domain, but is not itself considered a public domain, for reasons that need to be clarified. According to Rav, a צורת הפתח is required on one side and a pole or beam is sufficient on the other.  According to Shmuel, one side requires doors and the other can make do with a pole or beam.

3.       A מבוי that is only open on one side- This is the case we have been discussing from the beginning of the masechta, and either a pole or a beam on the open side is sufficient.

I have a few questions on the שקלא וטריא (give and take/flow) of the sugya, among them

1.       The Gemara initially rejected the simple interpretation of the first Beraisa based on the second Beraisa’s rejection of Rabbi Yehuda’s lenient view.

Although the Gemara later admits that one can retort that the views are not equivalent, and Rabbi Yehuda was more lenient than Beis Hillel who requires doors, it seems strange that it did not immediately see that.

2.       In addition, Rabbi Yehuda’s view making do with either a pole or a beam on both sides seems even more lenient than the most lenient view  seen in the first beraisa, namely that of the Tana Kama who at least required a צורת הפתח on one side.

As such, Even if we found a way to explain why the Gemara initially thought that the second Beraisa was a good proof against the simple explanation of the first, we need to explain why the Gemara assumes that it is at least a proof for the more stringent view of Chananya requiring doors. Surely all it proves is that a beam or a pole on both sides is not sufficient?

3.       Once the second Beraisa is rejected as a proof against the simple understanding of the first Beraisa, Rabbi Yochanan’s statement about Yerushalayim is brought to show that even Beis Hillel according to Chananya are too lenient.

Yet Rabbi Yochanan was only an Amora, and his view was only reported by another Amora. Is such a view authoritative enough to reject the simple meaning of a Beraisa and interpret it to refer not to a real public domain but rather a מבוי open on two sides to one?

Perhaps one can answer based on the fact that Rabbi Yehuda holds that an area enclosed on two sides is already considered a private domain on a biblical level.

As such, it is the equivalent to him of an area enclosed on 3 sides according to the majority opinion.

If the Chachamim rebuked Rabbi Yehuda for allowing such an area to be enclosed with just a pole or a beam, it could be that they are saying that even according to his lenient definition of a public domain, such an area is still a public domain on a rabbinic level and requires at least a צורת הפתח on one side.

It follows that according to Chachamim who consider such an area to be a proper public domain even on a biblical level, a צורת הפתח  would not be sufficient and doors would be needed, at least on one side, and possibly on both.

The Gemara then says that it is true that the second Beraisa implies that the Chachamim would require doors on one side, but who says that they would require these doors to be on both sides AND locked.

It then brings the statement of Rabbi Yochanan to prove that they would indeed. Although Rabbi Yochanan is an Amora, his statement is based on a reinterpretation of the first Beraisa, and given that no other Amora of his stature has suggested sticking to the simple interpretation, we need to consider his view as authoritative and discover what this reinterpretation is.

This is only my own analysis of the sugya, but a look at the various Rishonim will show that these issues are discussed, and similar answers are given.

What is a רשות הרבים (public domain.)

Now that we have seen that making an eruv in a true public domain is almost impossible, we can see that attempting to make an eruv in a busy and crowded city is fraught with difficulty.

The key to understanding where this could be possible is understanding what makes an area a public domain.

Given that the prohibition of transferring from domain to another or 4 אמות  within a public domain is derived from the mishkan in the biblical מחנה ישראל (camp of Israel,) it follows that the properties of this camp should serve as  guidelines for what is considered a public domain.

Rashi, on our daf, gives various criteria, which in his view, were shared by the public domain in the desert:

1.       It needs to be at least 16 אמות wide (approximately 8 metres)

2.       It needs to be a city where at least 600,000 people are present (שמצויין בה שישים רבוא)

3.       If it is walled on all sides, it needs to have two gates on opposite sides with a public thoroughfare running from one to the other.

What Rashi does not tell us here is what happens if an area in a city fulfills all the requirements, but another area does not. He also does not tell us if the city requires 600,000 to be there all the time, or only at certain times.

A major issue raised by Tosfos on our daf, is how the second requirement can be derived from the biblical camp.

We already learnt (Shabbos 99 and see our post on that daf) that the area underneath the wagons was also considered part of the public domain, and there were certainly not 600,000 people there. In addition, the number 600,000 referred only to the adult male population in the camp, and once women and children were included, it would have been far higher.

Although Rabbeinu Tam explains that the area under the wagons was indeed used by all the people when they travelled, and we use the number 600,000 because it is the only number actually mentioned in the text, other Rishonim such as the Rambam do not make mention of the 600,000 requirement at all, possibly for these reasons.

One could possibly explain alternatively  that Rashi did not mean that all areas of the public domain needed to be frequented by 600,000, but if the area as a whole was indeed frequented by that number of people, all areas in it are also considered part of the same public domain. Perhaps this is part of what Rabbeinu Tam meant.

If this true, how we define which areas are considered part of this public domain requires more information, but it seems clear that the area underneath the wagons was indeed part of the biblical camp.

All these issues guide the debate regarding where an eruv can and cannot be built, and it is not surprising that there different, sometimes extreme views on either side regarding whether one may or may not rely on eruvim in bigger cities that are subject to these doubts.