All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
The Prophetic narration which you mentioned proves that it is only when saying Allaahu Akbar to start the prayer that the praying person raises his hands as it reads: "…then he does not raise his hands again until he
finishes the prayer."
However, this narration is classified by some scholars
as weak such as Abu Daawood, Al-Bukhari and Al-Albaani
.
The authentic narrations confirmed from the Prophet
prove that he
used to raise his hands when bowing and when raising from the bowing position as well. For more benefit, please refer to Fataawa 87198 and 84676.
Allaah Knows best.