Sahih Muslim 1106
صحيح مسلم#1106SahihThis hadith has been narrated by Ja'far b. Rabi' with the same chain of transmitters. And in the narration transmitted by 'Amr b. al-Harith (the words are):" When the Messenger of Allah (rtiay peace be upon him) prostrated, he spread out his arms so that the whiteness of his armpits was visible." And in the narration transmitted by al-Laith (the words are:" When the Messenger of Allah (ﷺ) prostrated. he spread his hands from the armpits so that I saw their whiteness
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: 4:268