However, with regard to the contradiction between the one ruling concerning a person and the other ruling concerning a person, it is difficult, for one baraita states that one may not use a person as the wall of a sukka, while the other says that one may use a person as a wall and even states explicitly that he may do this: So that he may eat, drink and sleep in the sukka. That implies that this is permitted even if it is the third wall that is missing.

The Gemara answers: With regard to the contradiction between the one ruling concerning a person and the other ruling concerning a person, it is also not difficult. Here, where it is prohibited, the baraita refers to a case where that person knowingly served as a partition; whereas here, where it is permitted, it refers to a case where that person unknowingly served as a partition, which is not the usual manner of building. This is not the case with regard to utilizing a utensil as a partition. Since the utensil lacks knowledge, it is considered a partition regardless of how it is placed, and it is prohibited in all cases.

The Gemara raises a difficulty: However, the case involving Rabbi Neḥemya, son of Rabbi Ḥanilai, was a case where people knowingly served as a partition, as the people were instructed to go out and serve as a human partition. The Gemara answers: In fact, that was a case where people unknowingly served as a partition, i.e., they were unaware why they were called, and were made into a partition without their knowledge.

The Gemara asks: However, Rav Ḥisda, who gathered the people to that spot, was in any case present knowingly. The Gemara answers: While Rav Ḥisda was there knowingly, he was not among the designated people who served as a partition.

The Gemara relates that there were these members of a wedding party who engaged the many people present to bring water in on Shabbat from a public domain to a private domain through walls comprised of people who knew that they were being used as partitions for that purpose. Shmuel instructed that they should be flogged. He said with regard to this matter: If the Sages said that a partition is effective when the people act unknowingly, does this mean that they would also say that this is permitted ab initio when they knowingly serve as a partition?

The Gemara relates that there were once these flasks lying in the market [ristaka] of Meḥoza on Shabbat and could not be moved. When Rava was coming from his discourse accompanied by a throng of people, his attendants brought the flasks into his house, as the crowd of people created human partitions, upon which the attendants capitalized for this purpose. On another Shabbat they wanted to bring them in again, but Rava prohibited them from doing so, reasoning: This is like the case where the people knowingly served as partitions, for presumably the people now knew that they were being used for this purpose, and it is therefore prohibited.

The Gemara further relates that Levi was brought straw through human partitions comprised of people who were unknowingly used for this purpose, and in the same manner Ze’eiri was brought fodder [aspasta], and Rav Shimi bar Ḥiyya was brought water.

MISHNA: With regard to one who was permitted to leave his Shabbat limit, i.e., he went out to testify that he had seen the new moon or for some life-saving purpose, and they said to him along the way: The action has already been performed, and there is no need for you to travel for that purpose, he has two thousand cubits in each direction from the location where he was standing when this was told to him.

If he was within his original limit, it is considered as if he had not left his limit, and he may return to his original location. The Sages formulated a principle: All who go out to battle and save lives may return to their original locations on Shabbat.

GEMARA: The Gemara asks: What is the meaning of the statement: If he was within his original limit, it is considered as if he had never left? Given that he has not left his original boundary, it is clear that he remains within his original limit. Rabba said: The mishna is saying as follows: If he was within his original limit, it is considered as if he had never left his house. He is allowed to walk two thousand cubits in each direction from his house.

The Gemara asks: It is obvious that if he remained within his limit, he is considered as if he were in his house. Why is this statement necessary? The Gemara answers: Lest you say that, since he moved from his place with intention to leave his limit and go elsewhere, he moved and nullified his original place of residence. If so, his original place of residence would no longer determine his Shabbat limit, and instead he would have two thousand cubits in each direction from the location where he was standing when he was told that he need not travel. Therefore, the mishna teaches us that it is nonetheless considered as if he had never left his house.

Rav Shimi bar Ḥiyya said that the mishna is saying as follows: If he left his original Shabbat limit, but the new limit of two thousand cubits in each direction that the Sages granted him is subsumed within his original limit, so that if he walks those two thousand cubits, he can return to within his original limit, then it is as if he had never left his original limit, and he may return to his house.

The Gemara comments: With regard to what principle do Rabba and Rav Shimi bar Ḥiyya disagree? One Sage, Rav Shimi, holds that the subsuming of Shabbat limits, i.e., if one’s original limit is subsumed within the new limit, one may pass from one to the other, is something significant and may be relied upon, whereas this Sage, Rabba, holds that it is nothing significant and cannot be relied upon.

Abaye said to Rabba: Do you not hold that the subsuming of Shabbat limits is something significant? And what if he established residence in a cave that has entrances at its two ends, which on the inside of the cave is four thousand cubits across, but atop its roof it is less than four thousand cubits across? Is it not the case that he may walk the entire length of the roof and two thousand cubits outside it in either direction? The entire interior of the cave is considered as if it were four cubits, and he is permitted to walk another two thousand cubits in each direction from each of its entrances. Consequently, he is permitted to walk along the roof, two thousand cubits from the eastern entrance in the direction of the western entrance and vice versa. However, since the distance across the roof is less than four thousand cubits, these two limits are subsumed within one another, and he is permitted to walk the entire length of the roof, given that when two limits are subsumed within one another, one may pass from one to the other.

Rabba said to Abaye: Do you not distinguish between a case where the person established residence within the airspace of partitions before Shabbat while it was still day, as in the case of the cave, and a case where he did not establish residence within the airspace of partitions before Shabbat while it was still day, as in the case of the mishna? The principle governing the Shabbat limits being subsumed in one another only applies in the former case, where both of the Shabbat limits were established before Shabbat, but not in the latter case, where the two limits were established at different times, one before Shabbat and one on Shabbat.

Abaye raised a difficulty: And in a case where he did not acquire his place of residence within those partitions before Shabbat, does the principle governing the subsuming of limits not apply?