TABARANI 6649:
from al-Sāʾib b. Yazīd —
"The third Adhan was ordered by 'Uthman when the number of people in Al-Madinah increased. The Messenger of Allah ﷺ only had one Adhan, and the Adhan on Friday was when the Imam sat down." (Using translation from Nasāʾī 1393)
الطبراني ٦٦٤٩:
عن الساءب بن يزيد —
إِنَّمَا أَمَرَ بِالتَّأْذِينِ الثَّالِثِ يَوْمَ الْجُمُعَةِ عُثْمَانُ حِينَ كَثُرَ أَهْلُ الْمَدِينَةِ وَلَمْ يَكُنْ لِرَسُولِ اللهِ ﷺ غَيْرُ مُؤَذِّنٍ وَاحِدٍ وَإِنَّمَا كَانَ الْأَذَانُ يَوْمَ الْجُمُعَةِ حِينَ يَجْلِسُ الْإِمَامُ
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