Narrated As-Saib bin Yazid: The person who increased the number of Adhans for the Jumua prayers to three was `Uthman bin `Affan and it was when the number of the (Muslim) people of Medina had increased. In the lifetime of the Prophet there was only one Mu'adh-dhin and the Adhan used to be pronounced only after the Imam had taken his seat (i.e. on the pulpit).

Narrated As-Saib bin Yazid: In the lifetime of the Prophet, Abu Bakr and `Umar, the Adhan for the Jumua prayer used to be pronounced when the Imam sat on the pulpit. But during the Caliphate of `Uthman when the Muslims increased in number, a third Adhan at Az-Zaura' was added. Abu `Abdullah said, "Az-Zaura' is a place in the market of Medina."