Narrated Abdullah ibn Abbas: The Prophet (ﷺ) said about a person who had intercourse with his wife while she was menstruating: He must give one dinar or half a dinar in alms. Abu Dawud said: The correct version says si: One dinar or half a dinar. Shu'bah (a narrator) did not sometimes narrate this tradition as a statement of the Prophet (ﷺ)

English translation · Sunan Abu Dawud