Sahih Muslim 546
صحيح مسلم#546SahihHumran b. Aban reported:I used to fetch water for 'Uthman for his purification. Never was there a day that he did not take a bath with a small quantity of water. And Uthman said: The Messenger of Allah (ﷺ) at the time of our returning from our prayer told us (certain things pertaining to purification). Mis'ar said: I find that it was afternoon prayer. He said: I do not know whether I should tell you a thing or keep quiet. We said: Messenger of Allah, tell us if it is good and if it is otherwise, Allah and His Apostle know better. Upon this he said: A Muslim who purifies (himself) and completes purification as enjoined upon him by Allah and then offers the prayers, that will be expiation (of his sins he committed) between these (prayers)
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: 2:13