Explanation: In Kesuvos (81), regarding [a Yavam] who wants to sell his brother's property [there is a lien on it for the Yevamah's Kesuvah], Rashi explained that the Mishnah in Gitin (55b) about one who bought from a man, and later bought from his wife, the sale is Batel;

We establish this to discuss [one of the] three fields.

Question (R. Shmuel): All the more so it discusses other property, like it connotes here!

Answer (Ri): His sale is Batel from when she collects the property. The three fields do not exclude other property. Even regarding the three fields, his sale stands until they are collected.

Defense (of Rashi): "His sale is Batel" connotes immediately. We ask what this excludes, that [for other property] she cannot say "I did so only to please my husband";

[We ask] if it excludes other property, that she cannot collect from it at all, [and answer that] all the more so [she can say that she agreed only to please her husband, for had she refused,] she will have enmity!

Implied question: Why didn't he say that it excludes other property, that the sale is not Batel immediately?

Answer: For this, there was no need to say "this is only for the three fields." Obviously, the sale is Batel only for the three fields, for everyone sells land with a lien [for his wife's Kesuvah]!

Rather, surely we need to establish it to discuss the three fields only to exclude other property. She cannot collect it at all.

Question (Rashba): How can you say that obviously, for other property the sale is not Batel immediately?

Before we establish it here for the three fields, we thought that we discuss other property, even though it teaches "his sale is Batel"!

Implied question: Why didn't it discuss one who sells his slave for Peros, like it says in Gitin (47b), one who sells his field for Peros?

Answer: It is not normal to sell a slave like this. Rather, he rents him to do Melachah.

Implied question: If [the Torah teaches that] we do not kill [one who struck his slave, if the slave] survives a day, all the more so [if he survives] two days!

Answer (Rashi on Shemos 21:21): What is a day that is like two days? It is me'Es la'Es (24 hours).

Implied question: (Perhaps he does not hold that Kinyan Peros k'Kinyan ha'Guf.) Rather, he expounds "Tachtav" (and now, the slave works for the seller)!

Answer: It says also "Kaspo" (and the slave belongs to the buyer). What would be [R. Meir's] source to say that the Torah is particular about "Tachtav" more than "Kaspo"? Rather, it is because he holds that Kinyan Peros is like Kinyan ha'Guf.

Question: If so, he should have said that the law of Yom Oh Yomayim does not apply to either master, like we find in Bava Kama (89b)!

Citation (89b - Beraisa #1): If Leah brought a slave into her marriage to be Melug property, if she destroys a tooth or eye (or a limb that will not recover), the slave goes free, but not if her husband destroys a tooth or eye.

Citation (cont. - Beraisa #2): He does not go free whether she or her husband destroys a tooth or eye.

We conclude that both Tana'im disagree with Takanas Usha (if a wife sold her Melug property and died, her husband takes it back from the buyers). They argue about whether Kinyan Peros (her husband has rights to use her property) is like Kinyan ha'Guf. Tana #2 holds that Kinyan Peros k'Kinyan ha'Guf, and Tana #1 holds that Kinyan Peros Lav k'Kinyan ha'Guf;

Inference: Considering Kinyan Peros k'Kinyan ha'Guf does not help so that the slave goes free due to the husband, rather, so that he does not go free due to the wife!

Answer #1 (Ri bar Baruch): The text [there] does not say "they argue about whether Kinyan Peros is like Kinyan ha'Guf", rather, "all disagree with the Takanah. They argue like the following Tana'im";

The Beraisa (#1) that says that [he goes free] due to her, but not due to him, is like R. Yehudah;

The Beraisa (#2) that says that [he does not go free,] not due to him and not due to her, is like R. Elazar, who says that neither has the law of Yom Oh Yomayim. Even both of them together cannot free him.

Support: This is why they disagree with Takanas Usha. (The Gemara previously said that Tana #1 holds that there was no enactment, therefore he is considered to be her slave);

According to R. Elazar, her sale has no effect. Therefore, according to R. Elazar Takanas Usha cannot apply, that they enacted that the husband takes from the buyer. According to him, there is no sale at all!

Answer #2: With difficulty, we can answer for the text in Seforim. There, it is reasonable that Kinyan Peros k'Kinyan ha'Guf helps only so that he does not go free due to a tooth or eye that the wife destroyed;

However, that he should go free due to the husband, it does not help, for his Kinyan Peros is not strong enough to uproot her k'Kinyan ha'Guf, through freeing the slave.

Answer #3: Kinyan Peros of the husband, who never owned anything in the Guf (permanent rights to the slave), is unlike Kinyan Peros of one who sold his slave on condition that he will [still] serve the seller for 30 days;

Initially he owned everything, and he still did not leave him, for the Peros are his.

Support: [Tosfos] distinguishes like this regarding an animal of Arnona [the tithe that the king takes] in Pesachim (6a DH Hasam);

What is difficult from Bechoros is explained there.

Support: We must say so. We cannot say at all that R. Meir holds that Kinyan Peros k'Kinyan ha'Guf, and there he holds [that the slave goes free] due to the man, but not due to the wife...

In Yevamos (66a) [Amora'im] argue about one who enters appraised property to her husband. She says "I will take back my Kelim for my Kesuvah", and he, who divorces her, says "I will [keep them, and] give to you money";

Citation (66a): R. Ami says that the law is with him (he has the option). Rav Yehudah says that the law is with her;

Citation (cont.): A Beraisa supports R. Ami. Slaves of Tzon Barzel go free due to a tooth or eye due to the man, but not due to the wife.

Question: What is difficult for Rav Yehudah? Perhaps even though the law is with her, they go free due him, but not due to her, because he holds that Kinyan Peros k'Kinyan ha'Guf! R. Meir holds like this even regarding Nichsei Melug!

Answer: Rather, surely Kinyan Peros does not help at all to be like Kinyan ha'Guf so that they should go free due him, like I explained.

Question: In Gitin (48a) we conclude regarding the argument of R. Yehudah and R. Shimon that all agree that Kinyan Peros k'Kinyan ha'Guf!

Answer: There, it says only that we cannot learn from here (we could say that both agree that Kinyan Peros k'Kinyan ha'Guf).

In Erchin (26b) the text says "I could say that R. Shimon holds that [Kinyan Peros] k'Kinyan ha'Guf. The text does not say "all agree that."

Implied question: Why don't we bring [the Beraisa] here in Gitin (48a)?

Answer: We prefer to bring that Tana'im argue about a field, similar to the argument of R. Yochanan and Reish Lakish there.

Explanation #1 (Rashbam): [We are lenient about Safek Nefashos] because it says "v'Shaftu ha'Edah v'Hitzilu ha'Edah."

Rebuttal (and Explanation #2): Even without this [verse], we do not kill due to Safek. Even money we do not take [from a Muchzak] amidst Safek!

Question (Riva): How does Ameimar compare the law of a sale to the law of Yom Oh Yomayim? If so, partners can never sell!

Citation (Bava Kama 90a): Who is the Tana of the following Beraisa? One who is half-slave and half-free, or the slave of two partners, does not go free due to outermost limbs. This is like R. Elazar;

If so, also here, the slave of two partners, they cannot sell him!

Answer: There we discuss two partners, one of whom owns the Guf, and the other owns the Peros, similar to one who sells his slave on condition that he will [still] serve the seller for 30 days;

A half-slave, half-free man refers to one who gave all his [redemption] money, and he is lacking only a Get Shichrur (document of freedom) to permit him to marry a free woman. [His master] does not own anything in his body;

However, if part of his body belongs to this [master], and part belongs to this, he goes out due to outermost limbs. [A master] would lose his share if he knocked out his tooth or blinded his eye, just like he can sell [his share].

Implied question: It says there "didn't R. Elazar say that he must be his exclusive Kaspo (property)? Also here, he must be his exclusive slave!"

Answer: We do not learn from the verse. Even without a verse, we learn outermost limbs from the law of Yom Oh Yomayim, just like we learn regarding a sale;

Rather, the Gemara says so. I.e. we require his exclusive slave.

Question (Rashba): What is difficult? We should say that really, [she must protest against] another man. This that we said that she must protest is when [her husband] wrote to her "I have no Din u'Devarim in your property and their Peros";

Then, she must protest, for she does not rely on him!

Answer (Rashba): In any case, she relies on him, since if she dies, he inherits her;

Even if he wrote "in your life and in your death", we hold like R. Shimon ben Gamliel, that if she died, he inherits her, in Kesuvos (83b).

Inference: However, if he ate part in the husband's lifetime, and part after the husband died, no. (She need not protest, for in any case he has no Chazakah.)

Implied question: Why is this different than one who ate one year in front of the father, and two years in front of the son (above, 42a)?

Answer: There, had he eaten three years in the father's lifetime, it would be a Chazakah.

Question: Why does it discuss such a case, that she sold it to him, and he sold it to me? It should have said that he is believed to say "I bought it from you"!

If it is obvious that he is believed, if so also now it is obvious that he is believed through a Migo.