What is the ruling on a man having intercourse with his wife during menstruation or post-childbirth bleeding (nifas), and what are the views of the four schools of thought (Hanbalis, Shafi'is, Hanafis, Malikis) on this, along with the most preponderant evidence?

Scholars have agreed on the prohibition of intercourse with a menstruating woman, based on the Almighty's saying: "So keep away from women during menstruation." It is permissible for a husband to enjoy his menstruating wife in areas above the navel and below the knee. This is the view of the Hanafis, Malikis, and Shafi'is, who cited what was narrated from Mu'adh ibn Jabal: "What is permissible for a man from his wife when she is menstruating? He said: What is above the izar (lower garment)." The Hanbalis, however, held the view that a man may enjoy his menstruating wife as he wishes, except for intercourse, based on the Prophet's (peace be upon him) saying: "Do everything except intercourse."

As for someone who has intercourse with his wife while she is menstruating, the majority (Hanafis, Malikis, and Shafi'is) held that there is nothing upon him except repentance. The Hanbalis, however, maintained the obligation of an expiation of a dinar or half a dinar, based on the hadith (definition): "He should give in charity a dinar or half a dinar." The most preponderant view is that of the Hanbalis due to the soundness of their evidence.