Salim narrated from his father (Abdullah bin Umar), who narrated in a marfu‘ manner that the Messenger of Allah, peace and blessings be upon him, said: "Bilal gives the call to prayer at night, so keep eating and drinking until the son of Umm Maktum gives the call to prayer."

It is narrated from Sayyidah Aisha (may Allah be pleased with her) that the Noble Prophet (peace and blessings be upon him) had two muezzins: Bilal and the son of Umm Maktum. So the Messenger of Allah (peace and blessings be upon him) said: "Bilal gives the call to prayer during the night, so keep eating and drinking until you hear the call to prayer of Ibn Umm Maktum." Qasim said: There was such an interval between their calls to prayer that one would descend and the other would ascend (for the call to prayer).