Musnad Ahmad

It is narrated from Sayyiduna Sa’ib bin Yazid that during the blessed era of the Prophet (peace be upon him), there was only one muezzin who would give the call to prayer (adhan) for all prayers and for Jumu’ah, etc., and he would also say the iqamah. When the Prophet (peace be upon him) would ascend the pulpit on the day of Jumu’ah, Sayyiduna Bilal would give the adhan, and when the Prophet (peace be upon him) would descend from the pulpit, he would say the iqamah. This continued during the time of Sayyiduna Abu Bakr as-Siddiq and Sayyiduna Umar, until the era of Sayyiduna Uthman arrived.