Sayyiduna Malik bin al-Huwayrith (may Allah be pleased with him) said: I saw the Messenger of Allah (peace and blessings be upon him): when he said the takbir he would raise both his hands until they were level with his ears, and he would do so also when he bowed and when he raised his head from bowing.
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 16677