Sahih Muslim | Book 35 | Hadith Number 6514

Narrated by Abu Malik Ashaja'i
Abu Malik Ashaja'i reported on the authority of his father that whenever a person embraced Islam, Allah's Messenger (may peace be upon him) instructed him to recite: "O Allah, grant me pardon, have mercy upon me, direct me to the path of righteousness and provide me sustenance.