Sunan Ibn Majah

It was narrated from Anas that:The Jews would not sit with a menstruating woman in a house, nor eat with her, nor drink with her. That was mentioned to the Messenger of Allah, then Allah revealed the words: ""They ask you concerning menstruation. Say: that is a harmful thing, therefore keep away from women during menses."" The Messenger of Allah said: ""Do everything except sexual intercourse