Sahih Muslim 1310
صحيح مسلم#1310SahihAnother version on the authority of Ibn Umar says:When the Messenger of Allah (ﷺ) sat for tashahhud, he placed his left hand on his left knee and placed his right hand on his right knee, and he formed a ring like (fifty-three) and pointed with his finger of attestation
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: 5:148