Sahih Muslim 834
صحيح مسلم#834SahihAnas 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
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 3:155