The Messenger of Allah (ﷺ) said: The nearest a servant comes to his Lord is when he is prostrating himself, so make supplication (in this state).

The Messenger of Allah (ﷺ) used to say while prostrating himself: O Lord, forgive me all my sins, small and great, first and last, open and secret.

The Messenger of Allah (may peace be upon him') often said while bowing and prostrating himself: Glory be to Thee, O Allah, our Lord, and praise be to Thee, O Allah, forgive me, thus complying with the (command in) the Qur'an.

I asked 'Ata': What do you recite when you are in a state of bowing (in prayer)? He said: Hallowed be Thou, and with Thy praise, there is no god but Thou. Son of Abd Mulaika narrated to me on the anthority of 'A'isha (who reported): I missed one night the Messenger of Allah (ﷺ) (from his bed). I thought that he might have gone to one of his other wives. I searched for him and then came back and (found him) in a state of bowing, or prostration, saying: Hallowed be Thou and with Thy praise; there is no god but Thou. I said: With my father mayest thou be ransomed and with my mother. I was thinking of (another) affair, whereas you are (occupied) in another one.

One night I missed Allah's Messenger (ﷺ) from the bed, and when I sought him my hand touched the soles of his feet while he was in the state of prostration; they (feet) were raised and he was saying: O Allah, I seek refuge in Thy pleasure from Thy anger, and in Thy forgiveness from Thy punishment, and I seek refuge in Thee from Thee (Thy anger). I cannot reckon Thy praise. Thou art as Thou hast lauded Thyself.

All Glorious, All Holy, Lord of the Angels and the Spirit.