Sahih Muslim
The Book Pertaining to the Remembrance of Allah, Supplication, Repentance and Seeking Forgiveness (Kitab Al-Dhikr)
Book Number: 035 / Hadith Number: 6560
Farwa' b. Naufal reported on the authority of 'A'isha that Allah's Mes- senger (may peace be upon him) used to supplicate (in these words):" O Allah, I seek refuge in Thee from the evil of what I did and from the evil of what I did not."