Section One
The Impediment of Lineage
The jurists are unanimous that the women who become forbidden on account of blood-relationship are the seven named in the Qur’an: mothers, daughters, sisters, paternal aunts, maternal aunts, nieces through one’s brother, and nieces through one’s sister.
They likewise agree that the word “mother” here denotes every woman from whom you descend, whether through your mother’s side or your father’s; that “daughter” refers to every female who descends from you, whether through a son, a daughter, or directly; and that “sister” covers every woman who shares with you one of your two parents—or both of them, that is, the father, the mother, or both together.
“Paternal aunt” designates any woman who is a sister of your father or of any male ancestor of yours; while “maternal aunt” is every woman who is a sister of your mother or of any female ancestor of yours. “Brother’s daughters” includes every female descended from your brother—through her mother, her father, or directly—and “sister’s daughters” includes every female descended from your sister, whether directly, through her mother, or through her father.
These seven categories are absolutely forbidden, and I know of no disagreement on the matter. Their textual basis is the Almighty’s words, “Prohibited to you are …” (al-Māʾidah 5:3) to the end of the verse. The scholars also concur that a blood-relationship which bars intimacy by marriage bars it equally by ownership through the right hand.
Section Two
The Impediment of Affinity (In-Law Relations)
The women forbidden by reason of affinity are four:
- the wives of one’s fathers, on the basis of His words, “Do not marry women whom your fathers married” (al-Nisāʾ 4:22);
- the wives of one’s sons, on the basis of His words, “and the spouses of your sons who are your own issue” (al-Nisāʾ 4:23);
- the mothers of one’s wives, on the basis of His words, “and your wives’ mothers” (al-Nisāʾ 4:23);
- one’s step-daughters, on the basis of His words, “and your step-daughters who are in your care, born of the wives with whom you have consummated marriage” (al-Nisāʾ 4:23).
Muslims agree that two of these become forbidden by the contract itself—namely the wives of fathers and the wives of sons—and that one becomes forbidden only by consummation, namely the wife’s daughter (the step-daughter).
They differ, however, on two points concerning her:
- Is it a condition that the step-daughter be in the husband’s care?
- Is mere sexual contact with the mother sufficient, or is actual intercourse required for the prohibition to take effect?
With respect to a man’s mother-in-law they also disputed whether she becomes forbidden by intercourse with the daughter, or whether the mere contract with the daughter suffices. A fourth question in this chapter is whether illicit intercourse produces the same prohibitions as a valid marriage or a marriage contracted on doubtful grounds.
Thus four issues arise:
Issue One: Is it a condition, for forbidding the wife’s daughter, that she be in the husband’s care, or is this not a condition? The majority hold that it is not a condition; Dāʾūd maintains that it is.
The dispute hinges on whether the Almighty’s words, “who are in your care” (al-Nisāʾ 4:23), constitute a qualifying description that affects the ruling, or whether they merely depict what is most commonly the case.
Accordingly, whoever says that the phrase merely describes what is usually found