It was narrated from ‘Abdullah bin ‘Umar that when the Messenger of Allah صلی اللہ علیہ وآلہ وسلم started to pray, he would raise his hands in level with his shoulders, and when he bowed and when he raised his head from bowing, he would raise them likewise and say “Sami’ Allahu liman Hamidah, Rabband wa-lakal-hamd (Allah hears those who praise Him, our Lord, to You be praise).” And he did not do that when he prostrated.(Sahih).