The Messenger of Allah ﷺ used to raise his hands to the level of his shoulders and say the takbir whenever he stood for the prescribed prayer. He would do the same when he finished his recitation and was about to bow, and again when he rose from bowing. He did not raise his hands at any point in his prayer while he was seated. When he stood up after the two prostrations, he would raise his hands in the same manner and say the takbir.
حدثنا الحسن بن علي حدثنا سليمان بن داود الهاشمي حدثنا عبد الرحمن بن أبي الزناد عن موسى بن عقبة عن عبد الله بن الفضل بن ربيعة بن الحارث بن عبد المطلب عن عبد الرحمن بن الأعرج عن عبيد الله بن أبي رافع
عن رسول الله ﷺ أنه كان إذا قام إلى الصلاة المكتوبة كبر ورفع يديه حذو منكبيه ويصنع مثل ذلك إذا قضى قراءته وأراد أن يركع ويصنعه إذا رفع من الركوع ولا يرفع يديه في شيء من صلاته وهو قاعد وإذا قام من السجدتين رفع يديه كذلك وكبر
[Its chain is hasan] Tirmidhi transmitted it, Supplications, chapter on that [the supplication, "I have turned my face towards Him who created the heavens and the earth..."], no. 3423, from Hasan bin Ali through this route, and he said, hasan sahih. Ibn Majah also narrated it, no. 864, and Ibn Khuzayma graded it sahih, no. 584.