Purification (Kitab Al-Taharah)

Dawud :: Book 1 : Hadith 264

Narrated Abdullah ibn Abbas:

The Prophet (peace_be_upon_him) 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.

Source materials are from the University of Southern California MSA site
Hadith eBooks converted from Imaan Star