Sahih Muslim 1451
صحيح مسلم#1451SahihAbu Musa reported:I and my companions who had sailed along with me in the boat landed with me in the valley of Buthan while the Messenger of Allah (ﷺ) was staying in Medina. A party of people amongst them went to the Messenger of Allah (ﷺ) every night at the time of the 'Isya' prayer turn by turn. Abu Musa said: (One night) we (I and my companions) went to the Messenger of Allah (ﷺ) and he was occupied in some matter till there was a delay in prayer so much so that it was the middle of the night. The Messenger of Allah (ﷺ) then came out and led them (Musa's companions) in prayer. And when he had observed his prayer he said to the audience present: Take it easy, I am going to give you information and glad tidings that it is the blessing of Allah upon you for there is none among the people, except you, who prays at this hour (of the night), or he said: None except you observed prayer at this. (late) hour. He (i. e. the narrator) said: I am not sure which of these two sentences he actually uttered. Abu Musa, said: We came back happy for what we heard from the Messenger of Allah (ﷺ)
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: 5:284