Hazrat Abdullah bin Amr bin al-As (may Allah be pleased with him) narrated that Hazrat Abu Bakr Siddiq (may Allah be pleased with him) said to the Messenger of Allah (peace and blessings be upon him), "O Messenger of Allah! Teach me a supplication that I may recite in my prayer." The Prophet (peace and blessings be upon him) said, "Recite this: 'O Allah! I have wronged myself greatly, and none forgives sins except You. So forgive me with forgiveness from Yourself. Surely, You are the Most Forgiving, Most Merciful.'"