I saw Messenger of Allah ﷺ opening the prayer with the Takbir and raising his hands to the level of his shoulders at the time of saying the Takbir, and on saying the Takbir for bowing he did the same; and when he said, "Samiʿa l-lahu liman hamidah ", he did the same and then said, "Rabbana wa laka lhamd." But he did not do the same on prostrating and on lifting the head from it." (Using translation from Bukhārī 738)  

رَأَيْتُ رَسُولَ اللهِ ﷺ إِذَا افْتَتَحَ التَّكْبِيرَ فِي الصَّلَاةِ رَفَعَ يَدَيْهِ حِينَ يُكَبِّرُ حَتَّى يَجْعَلَهُمَا حَذْوَ مَنْكِبَيْهِ وَإِذَا كَبَّرَ لِلرُّكُوعِ فَعَلَ مِثْلَ ذَلِكَ ثُمَّ إِذَا قَالَ «سَمِعَ اللهُ لِمَنْ حَمِدَهُ» فَعَلَ مِثْلَ ذَلِكَ وَقَالَ «رَبَّنَا وَلَكَ الْحَمْدُ» وَلَا يَفْعَلُ ذَلِكَ حِينَ يَسْجُدُ وَلَا حِينَ يَرْفَعُ رَأْسَهُ مِنَ السُّجُودِ