Sunan Abi Dawud Book 2, Hadith 357
The Messenger of Allah (ﷺ) taught us how to pray. He then uttered the takbir (Allah is most great) and raised his hands; when he bowed, he joined his hands and placed them between his knees. When this (report) reached Sa'd, he said: My brother said truly. We used to do this; then we were later on commanded to do this, that is, to place the hands on the knees.
If I were in front of the Prophet (ﷺ), I would see his armpits. Ibn Mu'adh added that Lahiq said: Do you not see, AbuHurayrah could not stand in front of the Prophet (ﷺ) while he was praying. Musa added: When he uttered the takbir, he raised his hands.
Abdullah ibn Mas'ud said: Should I not pray for you the way the Messenger of Allah (ﷺ) prayed? So he prayed, raising his hands only once.
Abu Dawud said: This is a summarized version of a longer narration and it is not authentic with this wording.