Yevamot

HE IS FORBIDDEN TO MARRY HER MOTHER, HER MOTHER'S MOTHER AND HER FATHER S MOTHER; HER DAUGHTER, HER DAUGHTER'S DAUGHTER AND HER SON'S DAUGHTER; AND ALSO HER SISTER WHILE SHE  IS ALIVE. THE OTHER BROTHERS, HOWEVER, ARE PERMITTED.  SHE  IS FORBIDDEN TO MARRY HIS FATHER AND HIS FATHER'S FATHER;  HIS SON AND HIS SON'S SON; HIS BROTHER AND HIS BROTHER'S SON. A MAN IS PERMITTED TO MARRY THE RELATIVE OF THE RIVAL OF HIS HALUZAH BUT IS FORBIDDEN TO MARRY THE RIVAL OF THE RELATIVE OF HIS HALUZAH. GEMARA. The question was raised: Were relatives of the second degree  forbidden  in the case of a haluzah as a preventive measure,  or not? Did the Rabbis forbid marriage with relatives of the second degree, as a preventive measure,  only in respect of a relative who is pentateuchally forbidden,  but in respect of a haluzah  the Rabbis did not forbid relatives of the second degree as a preventive measure, or is there perhaps no difference?  — Come and hear: HE IS FORBIDDEN TO MARRY HER MOTHER AND HER MOTHER'S MOTHER, but 'her mother's mother's mother' is not mentioned!  [No.] It is possible that the reason why this relative was omitted  is because it was desired to state in the final clause, THE OTHER BROTHERS, HOWEVER, ARE PERMITTED, and, were 'her mother's mother's mother' also mentioned it might have been presumed that the brothers are permitted [to marry] her mother's mother's mother only  but not her mother's mother or her mother.  Then let 'her mother's mother's mother' be mentioned, and let it also be stated: The brothers are permitted to marry all of them!  — This is a difficulty. Come and hear: SHE IS FORBIDDEN TO MARRY HIS FATHER AND HIS FATHER'S FATHER. 'His father's father,' at any rate, was mentioned. Is not this  due to  the levir who participated in the halizah, through whom she is the daughter-in-law of his  son?  — No; this  is due to the deceased through whom she is the daughter-in-law of his  son. Come and hear: AND HIS SON'S SON, Is not this  due to the levir who participated in the halizah through whom she is the wife of his  father's father?  — No; it  is due to the deceased through whom she is his  father's father's brother's wife.  But, surely, Amemar permitted the marriage of one's father's father's brother's wife!  — Amemar interprets that  to refer to the son of the grandfather.  If so, [HIS SON, AND SON'S SON] are the same as HIS BROTHER AND HIS BROTHER'S SON!  — Both his paternal brother and his maternal brother were specified. Come and hear what R. Hiyya taught:  Four [categories of relatives are forbidden]  Pentateuchally  and four Rabbinically.  His  father and his  son, his  brother and his  brother's son are Pentateuchally forbidden;  his father's father  and his mother's father,  his son's son  and his daughter's son  are forbidden Rabbinically.  'His father's father', at any rate, is mentioned here. Is not this  due to the levir who participated in the halizah through whom she is his son's daughter-in-law?  — No; it  is due to the deceased  whose son's daughter-in-law she is. Come and hear: 'His mother's father'.  Is not this  due to the levir who participated in the halizah through whom she is his  daughter's daughter-in-law?  — No; it  is due to the deceased  through whom she is his  daughter's daughter-in-law. Come and hear: 'And his son's son'.  Is not this  due to the levir who participated in the halizah through whom she is his father's father's wife?  — No; it  is due to the deceased  through whom she is his father's father's brother's wife. But, surely, Amemar permitted the marriage of one's father's father's brother's wife!  — Amemar explains that  to be due to the levir who participated in the halizah,  but is of the opinion that relatives of the second degree were forbidden as a preventive measure even in respect of a haluzah. Come and hear: 'And the son of his daughter'.  Is not this  due to the levir who participated in the halizah through whom she is his mother's father's wife?  — No; it  is due to the deceased  through whom she is his mother's father's brother's wife. But, surely, no prohibition as a preventive measure was made in respect of the second degrees of incest!  Consequently  it must be due to the levir who participated in the halizah,  and thus it may be inferred that relatives of the second degree were forbidden as a preventive measure even in the case of a haluzah. This proves it. A MAN IS PERMITTED etc. R. Tobi b. Kisna said in the name of Samuel: Where a man had intercourse with the rival of his haluzah the child [born from such a union] is a bastard. What is the reason? — Because she  remains under her original prohibition. Said R. Joseph: We also have learned [to the same effect]: A MAN IS PERMITTED TO MARRY THE RELATIVE OF THE RIVAL OF HIS HALUZAH. Now, if you grant that the rival is excluded  one can well understand why the man is permitted to marry her sister.  If it be maintained, however, that the rival has the same status as the haluzah, why [should her sister] be permitted [to him]? May it be suggested that this  furnishes an objection against R. Johanan who stated: Neither he  nor the other brothers are subject to kareth either for [the betrothal of] a haluzah or for [the betrothal of] her rival?  — R. Johanan can answer you: Do you understand it!  Is the sister of a haluzah Pentateuchally forbidden?  Surely Resh Lakish said: Here  it was taught by Rabbi that the prohibition to marry the sister of a divorced wife is Pentateuchal and that that of the sister of a haluzah is Rabbinical! Why is there a difference [in the law] between the one and the other?