Narrated `Abdullah bin `Umar: I saw that whenever Allah's Apostle stood for the prayer, he used to raise both his hands up to the shoulders, and used to do the same on saying the Takbir for bowing and on raising his head from it and used to say, "Sami`a l-lahu liman hamidah". But he did not do that (i.e. raising his hands) in prostrations.
Hadith Referenceصحيح البخاري / كتاب الأذان (صفة الصلوة) / 736
Hadith Gradingمحدثین:أحاديث صحيح البخاريّ كلّها صحيحة
Narrated Abu Qilaba: I saw Malik bin Huwairith saying Takbir and raising both his hands (on starting the prayers and raising his hands on bowing and also on raising his head after bowing. Malik bin Huwairith said, "Allah's Apostle did the same."
Hadith Referenceصحيح البخاري / كتاب الأذان (صفة الصلوة) / 737
Hadith Gradingمحدثین:أحاديث صحيح البخاريّ كلّها صحيحة