Study Sanhedrin folio 58A with parallel Hebrew-English text, traditional commentary, and modern study tools. Free access to Babylonian Talmud online.
who was not conceived in sanctity, as his parents were still non-Jews, but his birth was in sanctity, as his mother converted before his birth, he has maternal kinship, i.e., his relationship to his mother’s relatives is recognized, but he does not have paternal kinship.
How so? If he married his maternal half sister, who was born before him and converted, he must divorce her. Although by Torah law they are considered unrelated, as a convert is considered to be reborn and all his previous family relationships are disregarded according to halakha, the rabbis prohib
If she is his mother’s maternal half sister, he must divorce her. If she is his mother’s paternal half sister, R' Meir says he must divorce her, and the Rabbis say he may maintain her as his wife. As R' Meir would say: With regard to any forbidden relative who is forbidden due to maternal kinship,
And according to all opinions, he is permitted to marry his brother’s wife and his father’s brother’s wife, and all other relatives with whom sex are forbidden in the case of born Jew are also permitted to him. The expression: And all other relatives with whom sex are forbidden, is added to include
With regard to a non-Jew who married a woman and her daughter and they all converted, he may marry one but must divorce the other one; and he should not marry the second of them ab initio. If his wife, the daughter, died, he is permitted to maintain his mother-in-law as his wife. And some say tha