Musnad Ahmad 529:0

It was narrated from ‘Utbah ibn ‘Abd al-Sulami, Abu al-Walid, that the Messenger of Allah (ﷺ) said: "If a person were to fall on his face from the day he was born until he dies in the obedience of Allah, the Mighty and Majestic, he would consider it insignificant on the Day of Resurrection, and he would wish to be returned to the world so that he could have more reward and merit."