Sahih Muslim Book 35, Hadith Number 6574.
Chapter : Refuge from the evil of what one has done, and what one has not done.
This hadith has been narrated on the authority of ‘Asim b. Kulaib with the same chain of transmitters that Allah’s Messenger (may peace be upon him) said to me: Say: “O Allah, I beg of Thee righteousness and adhering to the straight path.”