The mosque which was founded on piety

 237. Abu Salamah bin Abdur-Rahman said: Abdur-Rahman bin Abu Sa´id Al-Khudri happened to pass by me and I said to him: ´´What did you hear your father saying about the mosque which was founded on piety?´´ He said: My father said: ´´I went to the Messenger of Allah salla alayhi wa sallam as he was in the house of one of his wives, and said: ´O Messenger of Allah! which of the two mosques in founded on Taqwa (piety)?´´ He took a handful of pebbles and threw them on the ground, and said: ´This is the very osque of yours.´´´ He said: ´´I bear witness that I heard your father making mention of it.´´