Sayyidah Aisha Siddiqa (may Allah be pleased with her) narrates: The Prophet Muhammad (peace and blessings be upon him) said: "Ibn Umm Maktum gives the call to prayer at night (that is, a little before true dawn), so you may continue eating and drinking until Bilal gives the call to prayer." Sayyiduna Bilal (may Allah be pleased with him) used to give the call to prayer when he saw the true dawn.