Sahih Muslim 1196
صحيح مسلم#1196SahihIbn Sa'd reported:I bowed and my hands were in this state, i. e. they were put together, palm to palm, and were placed between his thighs. My father said: We used to do like this but were later on commanded to place them on the knees
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: 5:36