Book of Allotment of Nights and Recalcitrance (qism and nushūz)

The obligation of allotting nights applies only to one’s wives. If a husband spends the night with one of them, the same duty remains toward the rest. Should he abstain from all of them, or from a single wife, he is not sinful, though it is recommended that he not leave them neglected.

A sick wife, a woman who is ratqāʾ (born with an imperforate hymen), a menstruating woman, and one in post-partum bleeding are all entitled to their share; a nāshiz (recalcitrant wife) is not.

If the husband has no separate house of his own, he circulates among them in their respective dwellings. If he does have an independent residence, it is preferable for him to go to them, even though it is permissible for him to summon them to him. The sounder view, however, is that it is forbidden for him to visit some wives and merely invite the others, except for a valid reason such as the nearness of the house he is going to or fear for that wife’s safety. It is likewise unlawful for him to take up permanent residence in the lodging of one wife and call the rest to him there, or to lodge two rival wives together unless they both consent.

He may reckon a night together with the day before it or the day after it as one turn; essentially the night is the unit and the day follows it. If he works at night and rests by day, like a watchman, he reverses the rule.

The wife whose turn it is not has no claim to his presence at night, save in necessity—such as a dangerous illness. If, on such an occasion, he stays for a long time, he must make that visit up; if his stay is brief, he need not. He may enter during the day to place belongings and the like, but should not linger. The sound position is that no make-up is required when he enters for a need, and that he may enjoy every form of intimacy short of intercourse. If he enters without any need, he must compensate the one whose turn he has infringed. Equal division of daytime residence is not obligatory.

The minimum share is one night, and that is preferable. Granting up to three consecutive nights is permissible; according to the school one may not exceed that number. The correct view is that lots must be drawn to decide which wife receives the first turn, though some say he may simply choose. He must not show preference in the length of a turn: a free wife, for example, receives no more than a slave wife.

A newly-wed virgin is allotted seven consecutive nights at the time of consummation, with no obligation to compensate the other wives; a previously-married bride is given three. It is recommended that he offer her the option of limiting it to three nights without make-up.