from a single household, i.e., husband, and everyone agrees that only one wife from each household may be taken in levirate marriage, as the verse states: “To build his brother’s house,” which is interpreted to mean that the remaining brother may perform levirate marriage with only one wife of his late brother and not with two. To take one in levirate marriage and exempt the other without any procedure, he may not do, as perhaps the levirate bond is not substantial enough to make the first brother’s widow like a married woman to the second brother. In that case this woman whose husband died first remains the wife of the first brother, and the second woman is the wife of the second brother. Then there would be two separate levirate obligations, and one could not exempt the other; they would be two yevamot who come from two households. Therefore, apparently even when levirate betrothal was performed Rabbi Shimon is uncertain whether or not the levirate bond is substantial.

And if you would say that by Torah law, indeed, one of them may be taken in levirate marriage and thereby exempt the other, and this was prohibited only by rabbinic law, this would be a rabbinic decree due to the concern lest those who were not aware of the details mistakenly say that in general if two yevamot come from two households then one is taken in levirate marriage and the other is exempt without anything. One might have thought that the reason Rabbi Shimon required the other woman to perform ḥalitza is to avoid the possibility of such a mistake.

But this cannot be, as Rabbi Shimon’s reason is mentioned explicitly in the baraita, and there he does not state that this is a decree of the Sages. Rather, his reason is due to the question with regard to the strength of levirate betrothal, specifically whether the status of marriage is achieved by levirate betrothal or not achieved by levirate betrothal. As it is taught in a baraita: Rabbi Shimon said to the Rabbis in explanation of his opinion that one of the women could enter into levirate marriage: If the levirate betrothal of the second brother is indeed levirate betrothal and is considered as a fully valid marriage, then the third brother is engaging in relations with the wife of the second brother when he takes her in levirate marriage. That is, if the levirate betrothal by the second brother has the same status as full marriage, then she becomes the wife of this second brother, and all previous connections are no longer relevant.

But if the levirate betrothal of the second brother is not levirate betrothal, i.e., it does not have the full status of marriage, then there was never in fact any connection between the two. If she is then taken by the third brother in levirate marriage, he would be engaging in relations with the wife of the first brother. From here one can conclude that the basis for Rabbi Shimon’s uncertainty is related to the questions concerning the strength of the levirate betrothal.

Abaye said to him: From here you cannot prove what Rabbi Shimon’s opinion was. Is there no difference to you between a levirate bond to a single yavam and a bond to two yevamim? Perhaps when Rabbi Shimon said that a levirate bond is substantial enough to render her like a married woman, this applies only when there is a single yavam. If these were the circumstances of the case discussed, that when one brother died there remained only one yavam, then because the obligation of levirate marriage would apply only to him, she would be considered his wife. But perhaps he held that if there were two yevamin, then no, she would not be considered a married woman, as here the bond would apply to both at once. Accordingly, Rabbi Shimon’s uncertainty is with regard to the case of a levirate bond with two yevamin.

The Gemara challenges: Does Rabbi Shimon differentiate between the case of one yavam and the case of two yevamin in the matter of a wife of a brother with whom he did not coexist? But it is taught in a baraita with regard to the wife of a brother with whom he did not coexist: Rabbi Shimon stated a principle: Whenever the birth of the third brother precedes the levirate marriage of the second brother, if this second brother dies and the yevama falls before the third brother, she does not perform ḥalitza and she does not enter into levirate marriage. In such circumstances she is the wife of a brother with whom he did not coexist. But if the levirate marriage preceded his birth, she either performs ḥalitza or enters into levirate marriage.

What, is it not referring to the case of a single yavam, and it is taught in a baraita: She does not perform ḥalitza and she does not enter into levirate marriage. Even if there is only a single yavam this is not considered full marriage, and she remains forbidden as the wife of a brother with whom he did not coexist. Consequently, she who is subject to a levirate bond is not like a married woman. The Gemara answers: No. it refers to a case of two yevamin.

The Gemara asks: But what, then, is the ruling for a single yavam? So too, one should say she either performs ḥalitza or enters into levirate marriage, as the woman who requires levirate marriage is like the wife of the second brother for all purposes. If so, rather than teaching the case when the marriage of the second brother precedes the birth of the third brother, that if this second brother dies and she falls before the third brother, she either performs ḥalitza or enters into levirate marriage, let Rabbi Shimon distinguish and teach the distinction within the situation itself and say: In what case is this statement said? When there are two yevamin. But if there is one yavam, she either performs ḥalitza or enters into levirate marriage.

The Gemara rejects this: No, the entire baraita is in reference to two yevamin and differentiates between various cases involving two yevamin, namely, the case where the birth of the third brother preceded the marriage of the second brother and the case where the marriage of the second brother preceded the birth of the third brother. The Gemara asks: Rather, what is the principle in this matter? If Rabbi Shimon is speaking of two yevamin and not a single yavam, then it makes no sense to speak of a principle, as the halakha is different in the case of a single yavam.

Moreover, Rav Oshaya raised an objection from that which was taught in a mishna (28b): If there were three brothers, two of whom were married to two sisters, or to a woman and her daughter, or a woman and her daughter’s daughter, or a woman and her son’s daughter, who are, in each case, two women who may not be married to the same person simultaneously, and subsequently these brothers who were married to relatives died, then those two women must perform ḥalitza and may not enter into levirate marriage. Since they both have a levirate bond to the third brother at the same time and he is prohibited from marrying both, they cause one another to be unable to perform levirate marriage. And Rabbi Shimon exempts them even from ḥalitza.

And if it enters your mind that Rabbi Shimon held that a levirate bond is substantial enough to make her like a married woman, then let the third brother consummate the levirate marriage to the widow of the first husband to die, since as soon as her husband dies she has a levirate bond with the other brothers and should be considered to be like his wife, and let the other be exempt as a result, as her levirate bond began only with the death of the second husband.

Rav Amram said: What is really the meaning of the word exempt used by Rabbi Shimon? Only the second is exempt. The Gemara objects: But it is taught in a baraita: Rabbi Shimon exempts both. From here it is clear that in his opinion a woman subject to a levirate bond does not have the same status as a married woman.

Rava said: In the case mentioned in that baraita, there were three brothers, two of whom died. Each of the deceased brothers had four wives who were related to the wives of the other brother as described in the mishna. One wife of the first brother was the sister of a wife of the second brother. Another wife was the mother of a wife of the second brother. Another was the daughter of the daughter of a wife of the second brother. And another was the daughter of the son of a wife of the second brother. When these brothers died, all eight women happened before the remaining brother for levirate marriage. When Rabbi Shimon deemed both of them exempt, he was referring to the second from this pair and the second from that pair. That is, since one of them was bound to the third brother her relative became exempt as a forbidden relative, and the other of the pair was her rival wife in each of the cases.

The Gemara comments: Rava was mistaken about there being four pairs. He mistakenly understood that the mishna spoke of two brothers who married four pairs of relatives. Why does the Gemara assume that he was mistaken? One piece of evidence is that the mishna teaches the case using the expression: Or, or. The mishna teaches: Or to a woman and her daughter, or to a woman and her daughter’s daughter, or a woman and her son’s daughter, meaning that not all of the pairs happened before a single yavam for levirate marriage. And further, the baraita should have said: Rabbi Shimon exempts all four of them, i.e., the four women married to the second brother.

And further, it is taught explicitly in a baraita that Rabbi Shimon exempts both of them from both ḥalitza and levirate marriage, as it is stated: “And you shall not take a woman to her sister, to be a rival to her” (Leviticus 18:18). From here it is derived that when two sisters are about to become rival wives one to the other, that is, at the moment they fall before one brother for levirate marriage, you do not have the option of taking even one of them. In other words, levirate marriage to either of them is not permitted, and therefore both are exempt and not only the second. Thus Rava’s explanation is rejected.

Rather, Rav Ashi said an alternative answer to the Gemara’s challenge: If these yevamot happened before him for levirate marriage one after the other, indeed it is so that the first woman bound is like a married woman, and she exempts the second, who is her close relative. However, here we are dealing with a case when both brothers died at once and so both women happened before him at once. And Rabbi Shimon holds in accordance with the opinion of Rabbi Yosei HaGelili, who said: It is possible to be precise. He held, contrary to the opinion of the Rabbis, that it was possible to be exact about measurements of time. Therefore, it is possible for two things to truly occur at once, and it is possible that both brothers died simultaneously.

Until this point the Gemara dealt with Rav Oshaya’s opinion stating that according to Rabbi Shimon’s statement, even in the case of one who was born before his brother’s levirate marriage the ruling of a wife of a brother with whom one did not coexist would not apply. However, Rav Pappa said: Rabbi Shimon disagreed in the case where the second brother performed levirate marriage and after that the third brother was born; however, where the third brother was born after the death of the first brother and after that the second brother performed levirate marriage Rabbi Shimon did not disagree. He agreed that in this case she would be forbidden to the newly born brother as the wife of a brother with whom he did not coexist.

As for the question that Rav Oshaya raised with regard to the apparent redundancy of the similar rulings in both the first mishna of the chapter and the mishna on 18b, it can be explained that both were necessary for the opinion of the Rabbis who prohibited marriage to the wife of a brother with whom one did not coexist in every case. The difficulty raised concerning the apparent redundancy of the first mishna, given the greater scope of the opinion revealed in the second mishna, can be explained by saying that the tanna teaches the mishna employing the style: Not only this but also that. That is, the mishna follows the stylistic principle of first teaching the obvious case and continues by saying that this principle applies not only in the obvious case but even in the less obvious case. If so, there is no need to assume that there is an additional dispute with Rabbi Shimon.

The Gemara continues: It is taught in a baraita in accordance with the opinion of Rav Pappa, and this is a conclusive refutation of the opinion of Rabbi Oshaya: If there were two coexisting brothers, and one died childless, and the second was about to perform levirate betrothal with his yevama but did not manage to perform levirate betrothal before his brother was born, and then the second brother died, then the first woman goes out and is free to remarry without ḥalitza or levirate marriage due to the fact that she was the wife of a brother with whom the third brother did not coexist, and the second either performs ḥalitza or enters into levirate marriage. She was never the rival wife of the widow of the first brother.

If the second brother performed levirate betrothal with her and afterward his brother was born, or if his brother was born and then he performed the levirate betrothal, and then he died, the first goes out and is free to remarry as the wife of a brother with whom he did not coexist, and the second, the wife of the second brother, must perform ḥalitza and may not enter into levirate marriage. This is because, due to the levirate betrothal, she is considered by the Rabbis to be the rival wife of a wife of a brother with whom he did not coexist.