“The Messenger of Allah ﷺ used to raise his hands at every Takbir (saying Allahu Akbar) in the obligatory prayer.” (Using translation from Ibn Mājah 861)
«أَنَّ رَسُولَ اللهِ ﷺ كَانَ يَرْفَعُ يَدَيْهِ مَعَ كُلِّ تَكْبِيرَةٍ فِي الصَّلَاةِ الْمَكْتُوبَةِ»