What is the wisdom behind the difference in the waiting period (Iddah) for a free woman and a slave woman after the death of the husband, where a free woman observes a period of four months and ten days, while a slave woman observes two months and five nights, as stated in the book "Minhaj al-Muslim" by Abu Bakr Jabir al-Jaza'iri?

Some scholars have confined the wisdom behind the waiting period (iddah) for a widow (four months and ten days) to verifying that the womb is free of pregnancy. This is because the male fetus usually moves in three months and the female in four, and ten days were added to account for the possibility of delayed fetal movement.

Al-Shawkani differed from the majority and leaned towards the view of the Zahiris, who held that there is no difference in the iddah between a free woman and a slave woman. However, the majority and all the Companions agreed that the iddah of a slave woman is half that of a free woman (two months and five days), by analogy with the halving of the punishment for zina (unlawful sexual intercourse) for a slave woman.

Ibn al-Qayyim held that the iddah is not only for the purpose of ensuring the womb is clear, but also for several other wisdoms, including: magnifying the status of the marriage contract, fulfilling the right of the husband and demonstrating the impact of his loss. Therefore, the iddah of death is obligatory immediately upon death, whether consummation occurred or not, and it is not merely for clearing the womb. The correct view is that it is a period of حرمة (sanctity/prohibition) for the termination of a marriage that had not yet reached its full completion. As for the iddah of a slave woman, it was halved because her hadd punishment is halved, and because the benefit derived from her by the husband is incomplete, and his desire for offspring from her is less since the child follows the mother in servitude, and because she is not exclusively for the husband, as he cannot travel with her without the permission of her master.