It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that when the Messenger of Allah (peace and blessings be upon him) returned from the expedition of Khaybar, and he mentioned the hadith, in which it says: Then the Messenger of Allah (peace and blessings be upon him) performed ablution and ordered Bilal (may Allah be pleased with him), and he gave the iqamah for the prayer, and he (peace and blessings be upon him) led them in the morning prayer.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 1893