The prophet Muhammad would raise both his hands up to his shoulder level when beginning prayer and when standing up again from bowing during prayer. He would say "Allah hears whoever praises Him. O our Lord, for You is the praise" when standing up from bowing. However, he did not raise his hands during prostrations.

1. PRAYER

2. Narrated Salim bin 'Abdullah: My father said, "Allah's Apostle used to raise both his hands up to the level of his shoulders when opening the prayer; and on saying the Takbir for bowing. And on raising his head from bowing he used to do the same and then say "Sami a-l-lahuLimanhamida, Rabbanawalaka-l-hamd." And he did not do that (i.e. raising his hands) in prostrations. (SahihBukhari, Volume 1, Hadith 702)