Abu Hurairah (RA) reported: 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.
Abu Hurairah said: The prophet ﷺ used to say when prostrating himself: “O Allah. Forgive me all my sins, small and great, first and last. “ the narrator Ibn al-sarh added: “open and secret. ”
Shaykh Umar Farooq Saeedi
878. Commentary: ➊ Supplications of this nature by the Messenger of Allah (sallallahu alayhi wa sallam) were for the purpose of expressing gratitude and servitude, and also served as instruction for the Ummah. ➋ From this supplication and those that follow, it becomes completely clear that the Messenger of Allah (sallallahu alayhi wa sallam) is neither the Knower of the unseen nor the absolute disposer of affairs; rather, he is the perfect servant of Allah and a commanded servant (bound by the command of Allah).
Source: Sunan Abu Dawood – Commentary by Shaykh Umar Farooq Saeedi, Page: 878