Jami` at-Tirmidhi 260
جامع الترمذي#260SahihAbbas bin Sahl [bin Sa'd] narrated:"Abu Humaid, Abu Usaid, Sahl bin Sa'd, and Muhammad bin Maslamah were once together and they were mentioning the Salat of Allah's Messenger. Abu Humaid said: 'I am the most knowledgeable among you of the Salat of Allah's Messenger: Allah's Messenger would bow and place his hands on his knees as if he was grasping them, and he would draw his forearms to hold them away from his sides
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirSahih
Al-AlbaniSahih
Bashar Awad MaaroufHasan Sahih
Zubair Ali ZaiIsnaad Sahih
In-book reference: 2:112