Sunan an-Nasai Book 11, Hadith 877

أَخْبَرَنَا سُوَيْدُ بْنُ نَصْرٍ، قَالَ أَنْبَأَنَا عَبْدُ اللَّهِ بْنُ الْمُبَارَكِ، عَنْ يُونُسَ، عَنِ الزُّهْرِيِّ، قَالَ أَخْبَرَنِي سَالِمٌ، عَنِ ابْنِ عُمَرَ، قَالَ رَأَيْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم إِذَا قَامَ إِلَى الصَّلاَةِ رَفَعَ يَدَيْهِ حَتَّى تَكُونَا حَذْوَ مَنْكِبَيْهِ ثُمَّ يُكَبِّرُ - قَالَ - وَكَانَ يَفْعَلُ ذَلِكَ حِينَ يُكَبِّرُ لِلرُّكُوعِ وَيَفْعَلُ ذَلِكَ حِينَ يَرْفَعُ رَأْسَهُ مِنَ الرُّكُوعِ وَيَقُولُ ‏ "‏ سَمِعَ اللَّهُ لِمَنْ حَمِدَهُ ‏"‏ ‏.‏ وَلاَ يَفْعَلُ ذَلِكَ فِي السُّجُودِ ‏.‏

It was narrated that Ibn Umar said:"I saw the Messenger of Allah (ﷺ), when he stood to pray, raise his hands until they were in level with his shoulders, then he said the takbir. He did that when he said the Takbir before bowing, and he did that when he raised his head from bowing and said: 'Sami Allahu liman hamidah (Allah hears those who praise Him).' Bu he did not do that during the prostration