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.
Sahih Muslim Book 4, Hadith 246
← Previous Hadith 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).

Sahih Muslim Book 4, Hadith 245 Next Hadith → 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.

Sahih Muslim Book 4, Hadith 247