صحيح البخاري

And narrated Abu Huraira: Whenever Allah's Messenger (ﷺ) stood for the prayer, he said Takbir on starting the prayer and then on bowing. On rising from bowing he said, "Sami`a llahu liman hamidah," and then while standing straight he used to say, "Rabbana laka-l hamd" (Al- Laith said, "(The Prophet (ﷺ) said), 'Wa laka l-hamd'." He used to say Takbir on prostrating and on raising his head from prostration; again he would Say Takbir on prostrating and raising his head. He would then do the same in the whole of the prayer till it was completed. On rising from the second rak`a (after sitting for at-Tahiyyat), he used to say Takbir.