MISHNA: In the case of one who betrothed one of two sisters and does not know which of them he betrothed, so that both are forbidden to him, he gives a bill of divorce to this one and a bill of divorce to that one due to the uncertainty. If the man who had betrothed one of these women died before he could give a bill of divorce, and he had one brother, that brother performs ḥalitza with both of them, but he may not take either in levirate marriage. This is because he does not know which woman is his yevama and which is forbidden to him as the sister of a woman with whom he has a levirate bond.

If the man who betrothed one of these women had two brothers, one of them performs ḥalitza with one of the sisters, but he may not enter into levirate marriage with her due to the possibility that she is the sister of a woman with whom he has a levirate bond. And one takes the other in levirate marriage if he so desires. If the two brothers married the two sisters before consulting the court, the court does not remove them from their marriage and they are permitted to remain married. The couple who performed levirate marriage second was even permitted to do so, since there was no longer any doubt about the levirate bond.

Furthermore, in the case of two unrelated men who betrothed two sisters: If this one does not know which sister he betrothed and that one does not know which sister he betrothed, this one gives two bills of divorce, one to each of the women, and that one gives two bills of divorce. If the two men died before they divorced, and this one had a brother and that one had a brother, then this brother performs ḥalitza with both of them, and that brother performs ḥalitza with both of them.

If this one had one brother and that one had two brothers, the single brother performs ḥalitza with both of them, and of the two brothers, one performs ḥalitza and one performs levirate marriage if he so desires. If they married the sisters before consulting the court, the court does not remove them from the marriage and they are not told to divorce them. If this one had two brothers and that one had two brothers, the brother of this one performs ḥalitza with one sister, and the brother of that one performs ḥalitza with one sister. The brother of this one who performed ḥalitza may take the woman who performed ḥalitza [ḥalutza] of that other’s brother in levirate marriage, and the brother of that second one who performed ḥalitza may take the ḥalutza of that other’s brother in levirate marriage.

If the two brothers performed ḥalitza with both wives before consulting the court, the two brothers of the second man may not takeeither sister in levirate marriage lest one marry the sister of a woman with whom he had a levirate bond. Rather, one performs ḥalitza and one performs levirate marriage if he so desires. If they married their wives before consulting the court, the court does not remove them from the marriage.

GEMARA: Learn from here in the mishna that betrothals that cannot ultimately lead to consummation are nevertheless betrothals. There is a dispute between Abaye and Rava in tractate Kiddushin with regard to a case of a betrothal that, due to some halakhic complication, can never be consummated. The cases in this mishna may not be consummated, since each of the two sisters is forbidden due to the uncertainty as to whether she is the woman he betrothed or the sister of the woman he betrothed. Therefore, both are forbidden to him. Nevertheless, the mishna instructs that he must give a bill of divorce to both of them. This implies that such betrothals are valid, in contrast to Rava’s opinion that betrothals that cannot ultimately be consummated are not betrothals at all.

The Gemara rejects this: With what are we dealing here? We are dealing with a case when at first both sisters were recognized and at the moment of betrothal he knew whom he betrothed; it was a betrothal destined for consummation. But later the two sisters were mixed up so that he was no longer certain which he betrothed. If so, there was not any flaw in the betrothal itself initially. The language of the mishna is also precise, as it teaches: And he does not know which of them he betrothed, but it does not teach: It is unknown completely. This implies that the matter was known at some time. The Gemara adds: Conclude from here that this is the case.

The Gemara asks: If so, what is the mishna teaching us in the segment of the mishna referring to the giving of two bills of divorce? That is obvious. The Gemara answers: It was necessary to teach the last clause of the mishna, as there it teaches: If he died and he had one brother, that brother performs ḥalitza with both of them; if he had two brothers, one performs ḥalitza and the other one enters into levirate marriage if he so desires. Specifically, one brother must perform ḥalitza first, and only subsequently the other brother may perform levirate marriage. But one brother may not enter levirate marriage first, before the other brother has performed ḥalitza, as he would thereby encounter the sister of a woman with whom he has a levirate bond.

The mishna says: In the case of two unrelated men who betrothed two sisters: If this one does not know which sister he betrothed and that one does not know which sister he betrothed, this one gives two bills of divorce, one to each of the women, and that one gives two bills of divorce. The Gemara asks: Learn from here that betrothals that cannot ultimately lead to consummation are valid betrothals. The Gemara rejects this: Here too, this is referring to a case where they were recognized and later mixed up. The language is also precise, as it teaches: And he does not know, meaning that he does not know now whom he betrothed, and it does not teach: It is unknown. The Gemara summarizes: Indeed, conclude this from here that this is the case.

The Gemara asks: If so, what does it come to teach us in relating that both of them must give bills of divorce? The Gemara explains: It was necessary to teach the last clause, where it says: If they died and this one had one brother and this one had two, the single brother performs ḥalitza with both of them. And of the two, one performs ḥalitza and one enters levirate marriage if he so desires.

The Gemara asks: That is obvious, as this is identical to the halakha taught in the first clause of the mishna. Why should this case be different from the previous case of two brothers? The Gemara answers: It is necessary to teach this lest you say the Sages should issue a decree in the case of two brothers due to the case of one brother. In a case of one brother he may only perform ḥalitza but may not enter into levirate marriage. Without this mishna one may have thought the same should be true for two brothers. This comes to teach us that they did not issue such a decree, and in this case one of them is allowed to enter into levirate marriage.

And this is specifically if the brother of one man first performs ḥalitza and subsequently the brother of the other man consummates the levirate marriage, but if he consummated the levirate marriage first, then no, that is prohibited. And why is that? He might be encountering the prohibition of a yevama to a member of the public. Possibly the woman he married was not his yevama but someone else’s yevama, and until the other man’s brother performs ḥalitza with her she is still forbidden to other men.

The mishna taught: If this one had two brothers and that one had two brothers, the brother of this who performed ḥalitza may take the ḥalutza of that other’s brother in levirate marriage, and the brother of that second one who performed ḥalitza may take the ḥalutza of that other’s brother in levirate marriage. The Gemara asks: Why do I need this as well? This clause is identical to that previous halakha. The Gemara answers: It is necessary lest you say: Let the Sages issue a decree lest he consummate the levirate marriage without the other first performing ḥalitza at all. This comes to teach us that such a decree is not issued. Rather, one of each pair of brothers can enter a levirate marriage.

The Gemara asks: In what way is this case different from that which we learned in a mishna (26a): If there were four brothers, and two of them were married to two sisters, and those married to the sisters died, then those two sisters perform ḥalitza but may not enter into levirate marriage with the remaining brothers, since each woman is the sister of a woman with a levirate bond to each of the brothers. Why not say here as well that each is the sister of a woman with a levirate bond?

The Gemara rejects this: How can these cases be compared?