Question: Why are Kusim Pesulim (forbidden to marry Yisraelim)?

Answer #1 (R. Yochanan): It is because they are Gerei Arayos (they converted only because lions were eating them).

Question: If someone did not convert l'Shem Shamayim, and afterwards he returned and converted l'Shem Shamayim, perhaps we do not accept him?!

Answer #2 (R. Yochanan citing R. Elazar): It is because if a Nochri or slave who had Bi'ah with a Bas Yisrael, the child is a Mamzer. (Their initial conversion was invalid, so they were still Nochrim. Some of them married Benos Yisrael, and the children were Mamzerim.)

Note: Surely R. Yochanan cites the Tana R. Elazar (ben Shamu'a), and not the Amora R. Elazar ben Pedas, his Talmid. R. Yochanan often cites Tana'im, e.g. R. Shimon and R. Shimon ben Yehotzadak. (PF)

Question: R. Akiva holds that [from the beginning] they were proper converts! They did not intend to guard all the Mitzvos.)

Answer #3: It is because they do Yibum with Arusos (Yevamos who fell from Eirusin), and exempt Nesu'os (they expound "Lo Sihyeh Eshes ha'Mes ha'Chutzah l'Ish Zar" to exempt Nesu'os).

Question: Rabanan say that there is no Mamzer from a Yevamah [l'Shuk]!

Note: Mamzerim can result from their mistake. If they exempted a Yevamah Nesu'ah, and David was Mekadesh her, and then the Yavam died, and Levi was Mekadesh her, they hold that she is still David's wife, and really, she is Levi's wife! However, it is unreasonable to disqualify all Kusim due to such a rare case. (She thinks that she is David's wife. Why would she accept Kidushin from Levi?!) We could have said Rabanan forbid due to a Nochri who had Bi'ah..., and R. Akiva forbids due to exempting Nesu'os; the Gemara had a better answer.

Answer #4: It is because they are not expert in details of laws of Gitin. (Often she remarries based on a Pasul Get.)

Question: R. Gamliel is Machshir their Gitin! (He holds that they are expert in details of laws of Gitin.)

Answer #5 (R. Yakov bar Idi citing R. Yochanan): It is because Kohanim of the Bamos mixed with them;

(R. Ila): "Va'Ya'as Kohanim mi'Ketzos ha'Am" - from the Kotzim (thorns) in the nation, and from the Pesulim in the nation.

Note: This connotes that Kotzim and Pesulim are different matters. Perhaps Kotzim alludes to lowly people, and Pesulim refers to lineage (Mamzerim). We know to expound Pesulim only due to 'mi'Ketzos.' (PF)

(R. Yakov bar Acha): [Our Mishnah is Machshir documents that enter Nochri courts, except for Gitei Nashim or Shichrurei Avadim,] because there is publicity to [what is done in] the courts. (If it were Pasul, people would know not to rely on it.)

Question: If so, even if both [witnesses] are Kusim (the Get should be Kosher)!

Answer: [Gitin] are different, for they are not expert in details of laws of Gitin. (We explained this like RAMBAN.)

Question: R. Shimon is Machshir [their Gitin. They must be expert in details of laws of Gitin!]

Answer (R. Ba citing R. Ze'ira): R. Shimon holds like R. Elazar. Just like R. Lazar says that even if there are no witnesses on [a Get], it is Kosher [through Edei Mesirah], so R. Shimon says that even if there are no witnesses on it, it is Kosher.

Question: If so, [he should be Machshir] even if it was done through commoners!

Answer: We must answer like R. Yakov bar Acha said - there is publicity to [what is done in] the courts [but not to what commoners do].

There was a document in Beis She'an. The witnesses were Nochrim.

(R. Yosi): R. Yochanan and Reish Lakish argued about it. One disqualified, and one was Machshir.

R. Acha explains that R. Yochanan disqualified, and Reish Lakish was Machshir.

Question: What is Reish Lakish's reason?

Answer #1: It is to avoid a monetary loss to Yisrael [the lender].

Question: Even if there is no loss to [the lender], there is a loss to [the borrower]!

Answer #2 (R. Yudan): It is lest we lock the door in front of people. [If we disqualify such documents,] tomorrow (i.e. in the future) he will seek to borrow, and he will not find [someone to lend, if Yisrael witnesses are not available].