What is the ruling on a husband divorcing his wife with a single, revocable pronouncement while she is at her family's home and in a state of menstruation, given the husband's ignorance of the prohibition of such an act? And what is incumbent upon him if he wishes to take her back, or if he does not?

Divorcing a menstruating woman after consummation is forbidden by scholarly consensus. The divorce takes effect even if the divorcer is unaware of its prohibition, and this is the view of the majority of jurists. If the divorce is revocable (first or second), the husband can take his wife back as long as she is within her waiting period (iddah). The iddah for a divorced menstruating woman is three complete menstrual cycles; for a non-menstruating woman, it is three months; and for a pregnant woman, it is until she gives birth. The return is effected by saying, "I have taken you back."

Jurists differ on the ruling concerning taking back a divorced woman during her menstruation. The Hanafis and Malikis hold it to be obligatory, while the Shafi'is and Hanbalis consider it desirable. According to the Malikis, the husband is compelled to take her back. If the husband takes her back before the end of the menstruation cycle during which she was divorced, he must keep her until she becomes pure. It is recommended to keep her until she menstruates and becomes pure again. If the iddah has expired, the husband is not commanded to take her back, and he may remarry her with the consent of both parties.