And the residents of a small city may not walk through an entire large city.

What is the reason for this difference? Is it not because these, the residents of the small city, their measure of two thousand cubits terminated in the middle of the large city, and therefore they may walk only to the end of their two thousand cubits; and these, the residents of the large city, their measure of two thousand cubits terminated at the far end of the small city, allowing them to walk through the entire city as though it were four cubits and complete the two thousand cubit measure of their Shabbat limit on the other side of the city?

And Rabbi Idi, who said that Rabbi Yehoshua ben Levi’s statement has no source, may hold that the mishna teaches the two cases with the same formulation. Just as it states: The residents of a large city may walk through an entire small city, it similarly states: The residents of a small city may walk through an entire large city. His version of the mishna did not state that the residents of a small city may not walk through an entire large city. And he establishes the mishna as referring to one who placed his eiruv inside the other city. Consequently, that city becomes his Shabbat residence, and he may walk anywhere in that city and an additional two thousand cubits beyond it. But we did not learn anything about one who was measuring two thousand cubits from his Shabbat residence outside the city, in which case it makes a difference whether the entire city is within his two thousand cubits or whether only part of it is within this limit.

The Gemara asks: And did we not learn in the mishna about one who was measuring? Didn’t we learn in the mishna: And as for one who is measuring his Shabbat limit, with regard to whom the Sages said that one gives him two thousand cubits, that applies even if the end of his measurement terminates in the middle of a cave? Although a cave has the status of a private domain, he may enter only the part of the cave that is within his two thousand cubits. This case is directly parallel to the case of one whose two thousand cubits end in the middle of a city.

The Gemara answers: Although there is a source for the case of one whose limit ends in the middle of a city, it was nevertheless necessary for Rabbi Yehoshua ben Levi to teach the case where one’s measure ends at the far end of the city, in which case the entire city is regarded as four cubits and the rest of the Shabbat limit is completed on the other side of the city, as we did not learn anything about such a case.

With regard to the mishna cited above, Rav Naḥman said: One who teaches the following in the second clause: The residents of a small city may walk through an entire large city, does not err in his rendering of the mishna. And one who teaches: The residents of a small city may not walk through an entire large city, also does not err. Both renderings are plausible.

Rav Naḥman explains: One who teaches: The residents of a small city may walk through an entire large city, does not err, as he establishes the mishna as referring to one who places his eiruv inside the other city. And one who teaches: The residents of a small city may not walk through an entire large city also does not err, as he establishes the mishna as referring to one who measures his Shabbat limit and arrives at the city from the outside.

And the mishna is incomplete and it teaches the following: The residents of a large city may walk through an entire small city, but the residents of a small city may not walk through an entire large city. In what case is this statement said? It was said with regard to one who was measuring his two thousand cubits from his Shabbat residence. But one who was in the large city and placed his eiruv in the small city, and similarly one who was in the small city and placed his eiruv in the large city, he may walk through the entire city in which he placed his eiruv and beyond it two thousand cubits.

Rav Yosef said that Rami bar Abba said that Rav Huna said: With regard to a city located on the edge of a ravine, if there is a barrier four cubits high in front of it, one measures its Shabbat limit from the edge of the ravine, as it is considered the border of the city. And if there is not a barrier four cubits high in front of it, the Shabbat limit is measured from the entrance of each person’s house, as the city is not considered a permanent settlement.

Abaye said to him: You told us with regard to this case that a barrier four cubits high is required. What is different about this case that it requires a barrier that is higher than all other barriers, which must reach a height of only four handbreadths?

He said to him: There, use of the place is not frightening; here, use of the place is frightening. Generally, partitions serve a symbolic function, and therefore it is sufficient for the partition to be four handbreadths high. In this case, however, it is frightening to stand along the edge of the ravine without a protective barrier, and therefore a barrier four cubits high must be constructed for the safety of the residents.

Rav Yosef said: From where do I derive to say this halakha? As it was taught in a baraita: Rabbi Yehuda HaNasi permitted the residents of Geder, situated at the top of a slope, to descend on Shabbat to Ḥamtan, situated at the bottom of the slope, but the residents of Ḥamtan may not ascend to Geder. What is the reason? Is it not because these, the inhabitants of Geder, constructed a barrier at the lower edge of their city, and these, the members of Ḥamtan, did not construct a barrier at the upper edge of their city? Consequently, the residents of Geder measured their Shabbat limit from their barrier, and Ḥamtan was included in their two thousand cubits. The residents of Ḥamtan had to measure their Shabbat limits from their homes, and therefore Geder was not within their two thousand cubit limit.

The Gemara relates that when Rav Dimi came from Eretz Yisrael to Babylonia, he said: This ruling was issued not due to their respective Shabbat limits, but rather because the residents of Geder would assault [metatreg] the residents of Ḥamtan. And what does it mean that Rabbi Yehuda HaNasi permitted the residents of Geder to descend to Ḥamtan, but not vice versa? He instituted this. In other words, this was not a halakhic ruling, but rather an ordinance instituted to protect the public welfare and prevent fighting.

The Gemara asks: What is different about Shabbat that Rabbi Yehuda HaNasi instituted this ordinance only for Shabbat and not for the rest of the week? The Gemara answers: Drunkenness is common on Shabbat, when people eat to their heart’s content. Therefore, there is a greater chance of violent behavior.

The Gemara asks: When the residents of Geder go to Ḥamtan, they will assault the residents there; of what use, then, is this ordinance? The Gemara answers, citing a popular saying: A dog that is not in its place will not bark for seven years. On its own turf, a dog barks readily, but it becomes scared in unfamiliar surroundings and remains silent. Similarly, the people of Geder are not nearly as bold when they visit Ḥamtan as they are in their own town.

The Gemara asks: If so, we should be concerned about the reverse scenario, that now too, the residents of Ḥamtan, in their home territory, will take revenge and assault the residents of Geder. The Gemara answers: The people of Geder would not be submissive to such an extent. While visiting Ḥamtan, they would not initiate fights, but they would certainly fight back if they were attacked. Consequently, the people of Ḥamtan would not dare initiate hostilities with them. Therefore, there is no concern about the safety of either group.

Rav Safra said: Geder was a city shaped like a bow, whose two ends were separated by less than four thousand cubits. The empty space of the bow was viewed as though it were filled with houses, and its Shabbat limit was measured from the imaginary bowstring stretched between the two ends of the bow. Consequently, Ḥamtan was included in its Shabbat limit, and the residents of Geder were permitted to go there on Shabbat. With regard to the inhabitants of Ḥamtan, however, that same area between the ends of Geder was viewed as empty space, and therefore the houses of Geder along the arc of the bow were beyond their Shabbat limit.

Rav Dimi bar Ḥinana said: The people of Geder were residents of a large city, and the people of Ḥamtan were residents of a small city. Consequently, the residents of the large city, Geder, could walk through all of Ḥamtan, the small city; but the residents of Ḥamtan could walk only through part of Geder, as explained previously.

Rav Kahana taught it that way, as stated previously; whereas Rav Tavyomi taught it more concisely, in this way: Rav Safra and Rav Dimi bar Ḥinana disagreed about the matter. One of them said: Geder was a city shaped like a bow; and one of them said: The people of Ḥamtan were residents of a small city and the people of Geder were residents of a large city.

MISHNA: The residents of a large city may walk through an entire small city, and the residents of a small city may walk through an entire large city, even if part of it is located more than two thousand cubits from their city. How so? One who was in a large city and placed his eiruv in a small city, or one who was in a small city and placed his eiruv in a large city, may walk through the entire city in which he placed his eiruv and another two thousand cubits beyond it, as the entire city is considered as though it were only four cubits.

Rabbi Akiva says: He has only two thousand cubits from the place of his eiruv, as the actual area of the city is included in the calculation. Rabbi Akiva said to the Rabbis: Do you not concede to me that one who places his eiruv in a cave has only two thousand cubits from the place of his eiruv, and that consequently the entire cave is not considered as merely four cubits?

The Rabbis said to him: When does this apply? When the cave has no residents. But if it has residents, it is considered as though it were only four cubits, and one may walk through all of it and another two thousand cubits beyond it. Consequently, the halakha with regard to an eiruv placed inside a cave is sometimes more lenient than the halakha governing an eiruv placed in the area above the cave. If one places his eiruv inside a cave that has residents, he has two thousand cubits beyond the cave; if he places it above the cave, where there are no residents, he has only two thousand cubits from the place of his eiruv.

And as for one who is measuring his Shabbat limit, with regard to whom the Sages said that one gives him two thousand cubits, that measurement applies even if the end of his measurement terminates in the middle of a cave. He may not walk further into the cave, even if the cave is inhabited.