Is repeating the two supplications: "O Allah, forgive me all my sins, the minor and the major, the first and the last, the apparent and the hidden," and "O Allah, I have wronged myself greatly, and none forgives sins except You, so grant me forgiveness from You and have mercy on me, for You are the Forgiving, the Most Merciful" in every prayer a Sunnah?

The first Hadith (definition) was narrated by Muslim from Abu Hurayrah that the Prophet, may Allah’s prayers and peace be upon him, used to say in his prostration: “O Allah, forgive me all my sins, the small and the great, the first and the last, the apparent and the hidden.” A Muslim should be keen to supplicate with this in all his prayers, both obligatory and voluntary.

As for the second Hadith: The Prophet, may Allah’s prayers and peace be upon him, taught it to Abu Bakr, and a Muslim should supplicate with it in his prayers generally. Scholars have differed regarding its place; some said: during prostration, some said: after the Tashahhud (definition) and before the Tasleem, and some said: generally throughout the prayer.