GEMARA: The Gemara asks: How could one become liable to bring multiple sin offerings? But Rabbi Meir does not hold that a prohibition takes effect where another prohibition already exists. The Gemara answers: Although he generally does not hold that a prohibition takes effect where another prohibition already exists, with regard to an expanded prohibition and a more inclusive prohibition, he does hold that it takes effect where another prohibition already exists.

Consequently, the ruling stated in the mishna applies in a case where one engaged in intercourse with his mother and thereby fathered a daughter, so that the prohibitions against engaging in intercourse with his daughter and with his sister come into effect simultaneously. If that daughter married his brother, then since a prohibition was added with regard to his other brothers, to whom she has now become forbidden, it is an expanded prohibition, and therefore a further prohibition is added with regard to him as well.

If she later married his father’s brother, then since a prohibition is added with regard to the sons of his father’s other brothers, a prohibition is also added with regard to him. If she becomes, or remains, a married woman, since a prohibition is added with regard to every man in the world other than her husband, a prohibition is added with regard to him as well. If she then becomes a menstruating woman, since a prohibition is added with regard to her husband, a prohibition is added with regard to him as well.

MISHNA: It is possible for one who engages in intercourse with his daughter’s daughter to be liable to bring sin offerings due to the unwitting violation of the prohibitions of engaging in intercourse with his daughter’s daughter, and his daughter-in-law, and the wife of his brother, and the wife of his father’s brother, and his wife’s sister, and a married woman, and a menstruating woman. Rabbi Yosei says: If the elder, i.e., the man’s father, who is the woman’s great-grandfather, transgressed and married her, the man would also be liable for engaging in intercourse with her due to the prohibition of intercourse with the wife of his father.

And likewise, it is possible for one who engages in intercourse with the daughter of his wife to be liable to bring six sin offerings, similar to one who engages in intercourse with his own daughter, for violating the prohibitions against engaging in intercourse with his wife’s daughter, his sister, the wife of his brother, the wife of his father’s brother, a married woman, and a menstruating woman. And it is possible for one who engages in intercourse with his wife’s daughter’s daughter to be liable to bring seven sin offerings, similar to one who engages in intercourse with his own daughter’s daughter, for violating the following prohibitions: Engaging in intercourse with his wife’s daughter’s daughter, his daughter-in-law, the wife of his brother, the wife of his father’s brother, his wife’s sister, a married woman, and a menstruating woman.

GEMARA: It is taught in the mishna that Rabbi Yosei says: If the elder, i.e., the man’s father, who is the woman’s great-grandfather, transgressed and married her, the man would also be liable for engaging in intercourse with her due to the prohibition against engaging in intercourse with the wife of his father. The Gemara asks: Is she permitted to marry the man’s father? She had already been married to the man’s father’s brother, and therefore even if she was widowed or divorced from him, marriage would not even take effect with the man’s father, to whom she is forbidden as the wife of his brother. Rabbi Yoḥanan said: The marriage can take effect in a case where she happened to become designated to him for levirate marriage, when his brother died without children.

The Gemara raises an objection: If so, that they were married legitimately through levirate marriage, what is the reason for Rabbi Yosei’s statement that he transgressed and married her? Rabbi Ya’akov said: It means that he transgressed by marrying her due to her status as his son’s daughter-in-law, which renders her a secondary relative, forbidden to him by rabbinic law, albeit not by Torah law. Consequently, it was prohibited for him to enter into the levirate marriage.

This is as it is taught in a baraita: One’s daughter-in-law is a forbidden relative by Torah law, and his son’s daughter-in-law is a secondary relative, prohibited to him by rabbinic law, and similarly, you find with regard to the daughter of his son, who is prohibited to him by Torah law, and with regard to the daughter of his son’s son, until the end of all generations; the daughter of his son’s son, or of his son’s grandson, etc. They are all secondary relatives, prohibited to him by rabbinic law.

The Gemara asks: And is Rabbi Yosei of the opinion that a prohibition takes effect where another prohibition already exists? But didn’t we learn in a mishna (Sanhedrin 81a): If one violated a transgression that renders him liable to two death penalties, he is sentenced to the harsher one. Rabbi Yosei says: He is sentenced according to the first prohibition that applied to him.

And it is taught in a baraita: In what case did Rabbi Yosei say that he is sentenced according to the first prohibition that applied to him? If his mother-in-law was widowed or divorced, and therefore forbidden to him only due to her status as his mother-in-law, and later she married and became forbidden as a married woman, and he engaged in intercourse with her, then he is sentenced to death by burning due to his violation of the prohibition proscribing intercourse with his mother-in-law, as this was the first prohibition to take effect.

By contrast, if she was a married woman, and then he married her daughter and she thereby became his mother-in-law, and he subsequently engaged in intercourse with her, he is sentenced to death by strangulation due to his violation of the prohibition against engaging in intercourse with a married woman, despite the fact that burning is considered the more severe death penalty. This proves that Rabbi Yosei maintains that a prohibition does not take effect where another prohibition already exists.

Rabbi Abbahu said: Rabbi Yosei concedes that in the case of an expanded prohibition it takes effect even when another prohibition already exists. Consequently, he maintains in the mishna that the prohibition against intercourse with the wife of his father applies in addition to the previously existing prohibitions. And similarly, when Ravin came from Eretz Yisrael he said that Rabbi Yoḥanan says: Rabbi Yosei concedes with regard to an expanded prohibition.

The Gemara asks: What expanded prohibition is there here? The Gemara answers: The expanded prohibition applies when there is another son of the grandfather, i.e., another son of the father of the subject of the mishna. Consequently, since a prohibition against intercourse with the woman is added with regard to his father’s other son, when his father marries this woman, another prohibition against intercourse with her is added with regard to him as well.

MISHNA: It is possible for one who engages in intercourse with his mother-in-law to be liable to bring seven sin offerings for doing so, due to the unwitting violation of the prohibitions of engaging in intercourse with his mother-in-law, and his daughter-in-law, and the wife of his brother, and the wife of his father’s brother, and his wife’s sister, and a married woman, and a menstruating woman. And likewise, the same applies with regard to one who engages in intercourse with the mother of his father-in-law or with the mother of his mother-in-law.

Rabbi Yoḥanan ben Nuri says: It is possible for one who engages in intercourse with his mother-in-law to be liable due to the unwitting violation of the prohibitions of engaging in intercourse with his mother-in-law, and the mother of his mother-in-law, and the mother of his father-in-law. The Rabbis said to him: Those three prohibitions are all one category of prohibition, derived from the same verse: “You shall not uncover the nakedness of a woman and her daughter; you shall not take her son’s daughter, or her daughter’s daughter” (Leviticus 18:17). Consequently, one is not liable to bring separate sin offerings for violating these prohibitions.

GEMARA: Rabbi Elazar says that Rabbi Hoshaya says: Rabbi Yoḥanan ben Nuri and Sumakhos said the same thing. With regard to Rabbi Yoḥanan ben Nuri, this is referring to that which we stated in the mishna. With regard to Sumakhos, what is the equivalent ruling that he stated? It is the following ruling, as we learned in a mishna (Ḥullin 82a):