(Imām Bukhārī narrates): Ibn Muqatil narrated to us, he said: 'Abdullah informed us, he said: Abu Bakr bin 'Uthman bin Sahl bin Hunaif informed us from Abi Umamah bin Sahl bin Hunaif, he said,

"I heard from Hadhrat Mu'awiyah bin Abi Sufyan (may Allāh be pleased with them both) on the pulpit, when the mu'adhdhin said: 'Allāhu Akbar, Allāhu Akbar,' Hadhrat Mu'awiyah said: 'Allāhu Akbar, Allāhu Akbar.' When he said: 'Ashhadu an la ilaha illallah,' Hadhrat Mu'awiyah said: 'And I (also say it).' And when he said: 'Ashhadu anna Muhammadar Rasulullah,' Hadhrat Mu'awiyah said: 'And I (also say it).' And when he finished the adhan, Hadhrat Mu'awiyah said: 'O people! Indeed I heard from the Messenger of Allāh ﷺ in this gathering: When the mu'adhdhin gives the adhan, say what you have just heard from me.'"