I saw the Messenger of Allah ﷺ, when he began the prayer, raise his hands until they were level with his shoulders, and he would do so when he bowed and when he raised his head from bowing. Ibn Abu Umar added in his version, "But he would not raise them between the two prostrations."
حدثنا قتيبة وابن أبي عمر قالا حدثنا سفيان بن عيينة عن الزهري
رأيت رسول الله ﷺ إذا افتتح الصلاة يرفع يديه حتى يحاذي منكبيه وإذا ركع وإذا رفع رأسه من الركوع وزاد ابن أبي عمر في حديثه وكان لا يرفع بين السجدتين
Graded muttafaq alayhi (agreed upon), and reported by Muslim, Prayer, chapter on the recommendation of raising the hands level with the shoulders, etc., hadith 390, from the report of Sufyan bin Uyayna, and by Bukhari, hadith 735, regarding the takbir of ihram and the ruku, the report of Zuhri via this same chain, and it is mutawatir from Zuhri, may Allah have mercy on him.