Yahya related to me from Malik from Muhammad ibn Umara from Muhammad ibn Ibrahim that the mother of the son of Ibrahim ibn Abd ar- Rahman ibn Awf questioned Umm Salama, the wife of the Prophet, may Allah bless him and grant him peace, and said, "I am a woman who wears a long skirt and (sometimes) I walk in dirty places." Umm Salama replied, "The Messenger of Allah, may Allah bless him and grant him peace, said, 'What follows (i.e. clean places) purifies it.' "