I heard Muawiya bin Abu Sufyan, while he was seated on the pulpit, when the muezzin gave the call to prayer.The muezzin said, "Allah is the greatest, Allah is the greatest."Muawiya said, "Allah is the greatest, Allah is the greatest."The muezzin said, "I bear witness that there is no god but Allah."Muawiya said, "And so do I."The muezzin said, "I bear witness that Muhammad is the Messenger of Allah."Muawiya said, "And so do I."When the call to prayer was completed, he said, "People, I heard the Messenger of Allah ﷺ in this very seat, when the muezzin called the prayer, say what you have just heard me say."
سمعت معاوية بن أبي سفيان وهو جالس على المنبر أذن المؤذن قال: الله أكبر الله أكبر، قال معاوية: الله أكبر الله أكبر، قال: أشهد أن لا إله إلا الله، فقال معاوية: وأنا، فقال: أشهد أن محمدا رسول الله، فقال معاوية: وأنا، فلما قضى التأذين قال: يا أيها الناس، إني سمعت رسول الله ﷺ على هذا المجلس- حين أذن المؤذن- يقول ما سمعتم مني من مقالتي.
Bukhari narrated it in the Book of Friday Prayer (914). He said, Ibn Muqatil told us, he said, Abdullah (that is, Ibn Mubarak) informed us, he said, Abu Bakr bin Uthman bin Sahl bin Hunayf informed us, from Abu Umama bin Sahl bin Hunayf, and he related the hadith.Bukhari gave this chapter the heading, "The imam responds while on the pulpit when he hears the call to prayer."Hafiz said, Among the benefits found in this hadith are learning knowledge and teaching it while the imam is on the pulpit, that the preacher responds to the muezzin while he is on the pulpit, and that the responder's saying "and I am likewise" or something similar is sufficient in responding to the muezzin.