Abdullah bin Muhammad bin Hanafiyyah says that once I went with my father to our in-laws, who were Ansar. When it was time for prayer, the host said, "O slave girl! Bring water for ablution so that I may pray and find comfort." When he saw that we were surprised at this, he said, "I heard the Prophet Muhammad (peace be upon him) say, 'O Bilal! Stand up and bring us comfort through prayer.'"