Sahih al-Bukhari · The Book of Adhan
59- بَابُ إِذَا لَمْ يَنْوِ الإِمَامُ أَنْ يَؤُمَّ ثُمَّ جَاءَ قَوْمٌ فَأَمَّهُمْ:
(59) Chapter. If the Imam has not had the intention of leading the prayer and then some persons join him and he leads them.
1 hadith · references 699–699
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