Implied question: (Why do we ask "what is the Chidush"?) This teaches that [Hezek Re'iyah] is considered damage!

Answer: The Gemara means, why does the Mishnah discuss when there is no Din Chalukah? (What do we learn from this?) It should teach [that Hezek Re'iyah is damage] when there is Din Chalukah! Even though they did not want to divide, they divide [and build a wall]!

Question: There is a Chidush! Even when there is no Din Chalukah, and one could say that he did not agree [to divide] if he will be obligated to make a wall [we do not say so. Since he agreed to divide, he must also make a wall], like it explained above (2b).

Explanation: We do not ask according to the opinion that "Mechitzah" means wall. We can say that they did Kinyan [Chalipin] and put a lien on their property to build the wall;

Rather, we ask according to the opinion that "Mechitzah" means wall, Kinyan does not help, for it is a mere Kinyan of words. It did not cross his mind that they acquired in directions.

Implied question: In Bava Metzi'a (94a), a Mishnah says that a Shomer Chinam can stipulate to be [liable for theft, loss and Ones,] like a borrower, and we establish it to be when they acquired from him! (Here we say that Kinyan Devarim does not help.)

Answer: That is not Kinyan Devarim. It is a full Kinyan. He obligates himself that if there is an Ones, he will pay.

Question (Ri): What does Rav Ashi come to add? Must he teach that Chazakah helps like Kinyan (Chalipin)?!

Answer (Ri): The Chidush is, even though he said below in Bava Basra (53a) that [if one who acquires land is] not in front of him (the original owner who sells or gives it), he must say to him "go make Chazakah and acquire";

Here, since they said "you take the north, and I will take the south", and he went and made Chazakah in it, each in his [portion], not in front of the other, it is as if they acquired in directions, even though they did not say "go make Chazakah and acquire."

Question #1 (R. Tam): Bricks are worse (weaker than rocks), and [a brick wall four Amos tall] stands with a width of three Tefachim!

Question #2: We see that walls of smooth rocks taller than four Amos endure with a smaller width!

Answer (R. Tam): Our Gemara means that higher will not stand like is proper for smooth rocks. People want to build a wall that will stand many years when they build with smooth rocks.

Explanation #1 (R. Tam): "Trak" is like Truki Gali (close the doors - Berachos 28a), and "Sin" is Sinai. I.e. it interrupts and closes off the Luchos, which were given at Sinai, which were in the Aron in the Kodesh ha'Kodoshim.

Explanation #2: Traksin means inside and outside. There was a Safek whether it has Kedushas Panim (like the Kodesh ha'Kodoshim), or of outside (like the Heichal), like we say in Yoma (51b).

Observation: We could have answered that due to the ceiling and plaster, a higher wall was able to stand, like we say below (3b).

Explanation: Now we do not need the first answer [that six Tefachim suffice for 30 Amos only if the wall reaches a ceiling].

Question: Perhaps we infer that there are bigger [bricks]! How do we infer [that there are smaller bricks]?

Answer (Ri): If there are no bricks less than three, but there are bigger, if so there was no need to say "a half-brick of three Tefachim";

It needed to teach only "an Ari'ah is a half-brick", and no more. We would calculate based on the smaller size, since the Shi'ur is not explicit.

Explanation #1: This is like when there are cracks, and it is permitted [to destroy the old Beis ha'Keneses before building the new one. Maharam - this Perush holds that there was one Beis ha'Keneses. At the end of summer, they destroyed it and rebuilt it for winter. At the end of winter, they destroyed it and rebuilt it for summer. This is like when there are cracks, for it was not proper to pray in it in its current state.]

Explanation #2 - Opinion #1: If there were two Batei Kenesiyos, in two places, of summer and winter, we discuss when they saw cracks in it. (If not, one may not destroy the old one before building the new one.)

Opinion #2: Since there is another Beis ha'Keneses, we are not concerned if they do not build this one.

Implied question: It says [that the two opinions argue about] when there is a[nother] place to pray (i.e. the one who is concerned for negligence forbids)!

Answer #1: [This is when the other place] is not a Beis ha'Keneses.

Answer #2: Here, due to cold and heat, we are not concerned for negligence. (Surely they will rebuild it in time, to avoid pain.)

Answer #3: Alternatively, in such a big time [from summer until winter, or vice-versa] we are not concerned for negligence.

Explanation: [We ask that] we should be concerned until they pray in it. (However, once they pray in it, we are not concerned lest they sell it, even for Pidyon Shevuyim.)

Question: We say (Tosfos Megilah 2:11) that one may not sleep in a Beis ha'Keneses, not a fixed or haphazard sleep!

Suggestion: [It was permitted because] this was in Bavel, and Rav Asi taught (Megilah 28b) that Batei Kenesiyos of Bavel were made conditionally;

There, Rashi explained that [the Tenai] affects what was taught above [there], that we do not eat or drink in them, or enter them when it is sunny to avoid the sun, or when it is raining to avoid the rain. Regarding [Batei Kenesiyos] of Bavel, it is permitted.

Rejection: It says there after this that Ravina and Rav Ada were asking teachings from Rava. A torrential rain came on them. They entered a Beis ha'Keneses;

They did not enter due to [desire to avoid] the rain, rather, because teachings need clarity [and they could not think clearly in the rain].

Summation of Rejection: This was a Beis ha'Keneses of Bavel. [According to Rashi,] they could enter due to the rain!

Answer: [Rav Ashi] did not literally bring his bed into the Beis ha'Keneses, rather, next to the Beis ha'Keneses, in a place where guests normally sleep and eat;

We say in Pesachim (101a), according to Shmuel, why do we say Kidush in the Beis ha'Keneses? It is to exempt guests from their obligation of Kidush, for they eat, drink and sleep in (i.e. next to) the Beis ha'Keneses.

Implied question: [We learned that Batei Kenesiyos of Bavel] were made conditionally. (What is the relevance of this?)

Answer (Ri): If they become desolate, they may do like they wish there, except for frivolity, like we say there.

Explanation: This is correct (anyone who claims to come from Beis Chashmonai is really a slave), for also Shmuel said so in Kidushin (70b).

Question: In Sotah (41a), it says that [Chachamim] said to Agripas [ha'Melech, who descended from Hurdus] "you are our brother." Rashi explained that they said "you are our brother", since his mother was a Yisraelis;

If so, since Hurdus' sons married Bnos Yisrael, why was he [due to being a descendant of Hurdus] a slave?

Shmuel himself holds that if a Nochri or slave has Bi'ah with a Yisraelis, the child is Kosher, in Yevamos (45a)!

Answer: We must say [unlike Rashi] that [Hurdus' sons] did not marry Bnos Yisrael. (Rather, they married slaves);

[Chachamim] called [Agripas] "our brother", since a slave is our brother in Mitzvos (also he is obligated in most of the Mitzvos. See also Tosfos Yevamos 45b.)

Explanation: The simple meaning of the verse does not exclude a slave, for he is your brother in Mitzvos. Rather, it excludes a Nochri;

Rabanan expound 'from the finest of your brothers' [to exclude slaves].

Explanation: He did not literally kill all of them, for there were still Bnei Beseirah, who were the Nesi'im when Hillel ascended from Bavel, like we say in Pesachim (66a);

Hillel was Nasi during Bayis [Sheni starting] 100 years before the Churban, like it says in Shabbos (15a);

The reign of Hurdus during Bayis [Sheni started] 103 years before the Churban, like it says in Avodah Zarah (9a).