Sahih Muslim 834
صحيح مسلم#834Sahihحَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ مُعَاذٍ الْعَنْبَرِيُّ، حَدَّثَنَا أَبِي، حَدَّثَنَا شُعْبَةُ، عَنْ عَبْدِ الْعَزِيزِ بْنِ صُهَيْبٍ، سَمِعَ أَنَسَ بْنَ مَالِكٍ، قَالَ أُقِيمَتِ الصَّلاَةُ وَالنَّبِيُّ صلى الله عليه وسلم يُنَاجِي رَجُلاً فَلَمْ يَزَلْ يُنَاجِيهِ حَتَّى نَامَ أَصْحَابُهُ ثُمَّ جَاءَ فَصَلَّى بِهِمْ .
Anas b. Malik reported:(The people) stood up for prayer and the Messenger of Allah (ﷺ) was talking in whispers with a man, and he did not discontinue the conversation till his Companions dozed off; he then came and led the prayer
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 3:155