O Allah! I have considerably wronged myself
Abu Bakr As-Siddiq, May Allah be pleased with him, reported:
"I requested the Messenger of Allah may the peace and blessings of Allah be upon him, to teach me a supplication which I could recite in my Salat (prayer). Thereupon he said, "Recite: 'Allahumma inni zalamtu nafsi zulman kathiran, wa la yaghfirudh- dhunuba illa Anta, faghfir li maghfiratan min 'indika, warhamni, innaka Antal-Ghafur-ur-Rahim (O Allah! I have considerably wronged myself. There is none to forgive the sins but You. So grant me pardon and have mercy on me. You are the Most Forgiving, the Most Compassionate)."
Abu Bakr, may Allah be pleased with him, used to supplicate Allah continuously by day and night. He used to fear Allah more than all of the companions of the Prophet, may the peace and blessings be upon him, so he was the most pious one after the Messenger of Allah.
Such a recognition if issued from the heart and uttered by the tongue, is the best of means to seek the pleasure of the Lord the Almighty, so that one gets what he asks from him, the Blessed and Exalted.
The righteous slave should remember so much this recognition, because it shows the slavery in its highest form and the deep need to the Creator.
Especially if it is said in the prayer that is the close link between the slave and his Lord, in which one shows the perfect submission, humiliation, and sticks his forehead and nose to the earth in honor of the greatness of his Lord and in obedience to his orders regardless of his position.
One should be keen to increase supplication during the prostration because it is the most likely position to have one`s supplication answered.