Sunan Abi Dawud

Narrated Abdullah ibn az-Zubayr: The Prophet (ﷺ) used to point with his finger (at the end of the tashahhud) and he would not move it. Ibn Juraij said: ""And 'Amr bin Dinar added: 'He (Ziyad) said: ""'Amir informed me from his father that he saw the Prophet (ﷺ) supplicating like that. And the Prophet (ﷺ) would brace himself with his left hand on his left knee