Abu Humayd, Abu Usayd, Sahl bin Saad, and Muhammad bin Maslama gathered together and discussed the prayer of the Messenger of Allah ﷺ.Abu Humayd said, "I am the most knowledgeable among you regarding the prayer of the Messenger of Allah ﷺ. When the Messenger of Allah ﷺ bowed, he placed his hands on his knees as though gripping them, and he held his arms out taut, keeping them away from his sides."
حدثنا محمد بن بشار بندار حدثنا أبو عامر العقدي حدثنا فليح بن سليمان حدثنا
اجتمع أبو حميد وأبو أسيد وسهل بن سعد ومحمد بن مسلمة فذكروا صلاة رسول الله ﷺ فقال أبو حميد أنا أعلمكم بصلاة رسول الله ﷺ إن رسول الله ﷺ ركع فوضع يديه على ركبتيه كأنه قابض عليهما ووتر يديه فنحاهما عن جنبيه
[Its isnad is hasan] Abu Dawud narrated it in "The Book of Prayer," chapter "Beginning the Prayer," Hadith 734, from the hadith of Abu Amir Abdul-Malik bin Amr Aqdi, with this same chain, and Ibn Khuzayma graded it sahih, Hadith 589, 608, 637, 689, as did Ibn Hibban, Hadith 494, and others. It mentions the raising of the hands (see Sunan Ibn Majah, Hadith 863, in my edition). Part of this hadith comes up again at Hadith 293.There is also a report on this subject from Anas [see Nasb Raya, 1/372, 373].