Hazrat Qasim bin Muhammad (may Allah have mercy on him) narrates that I asked Sayyida Aisha (may Allah be pleased with her) about a man who goes to his wife (has intercourse with her), then puts on his clothes and sweats in them, do they become impure? She replied that a woman used to keep a piece or pieces of old cloth, and when this happened (i.e., when the man had intercourse), the man would clean the impurity with that piece, and he did not think that (due to the sweat) his clothes would become impure.