and ḥāʾiḍ—without the feminine tāʾ—is the active participle that denotes a woman who is menstruating; the tāʾ is omitted because menstruation applies exclusively to women.

– “by one dīnār”: the dīnār was a gold coin; the Islamic dīnār weighed four and a quarter grams of gold (4.25 g).

Points derived from the ḥadith

1. Intercourse with a menstruating woman is prohibited. Allah, Exalted be He, says: “So keep away from women during menstruation, and do not approach them until they are purified; but when they have cleansed themselves, then go in to them from where Allah has commanded you” (Qur’an 2:222).
2. Whoever has intercourse with his wife while she is menstruating must give an expiation in charity: either one dīnār or half a dīnār.
3. The prohibited act is penetration. Fondling a menstruating woman outside the vagina is permissible, as stated earlier, and the previously cited ḥadith of ʿĀʾishah attests to that.
4. Shaykh al-Islām Ibn Taymiyyah said: The obligation of expiation for intercourse during menstruation conforms to analogical reasoning even if no text existed, for transgressions involving normally lawful acts that become forbidden in certain states—such as intercourse while fasting, while in iḥrām, or during menstruation—carry expiations, whereas intrinsically unlawful acts, like oppression or fornication, have no prescribed expiation.

Scholarly disagreement
The jurists have differed concerning the expiation for intercourse during menstruation:
• Imām Aḥmad held that it is obligatory upon the man who penetrates a menstruating woman, and upon the woman as well if she consented. The expiation is, at one’s choice, a full dīnār or half of one, in accordance with the ḥadith.
• The other three imams maintained that no expiation is due from either of them. Al-Tirmidhī remarked that this is the position of the scholars of the major centres.
• Ibn Kathīr said: He should seek Allah’s forgiveness, for liability is presumed clear unless evidence establishes otherwise.