Sayyiduna Imran bin Husayn (may Allah be pleased with him) narrates from his father (Husayn bin Ubayd) that he came to the Prophet (peace and blessings be upon him) before accepting Islam, and when he was about to leave he asked: What should I say (in supplication)? He (peace and blessings be upon him) said: "Say: 'Allahumma qini sharra nafsi, wa'zim li 'ala rushdi amri' (O Allah, protect me from the evil of my own self, and grant me firmness upon right decision and guidance in my affairs)." He said these words and then left without accepting Islam. Later he accepted Islam and said: O Messenger of Allah! Now that I have accepted Islam, what should I say? He (peace and blessings be upon him) said: "Say: 'Allahumma qini sharra nafsi, wa'zim li 'ala rushdi amri, Allahumma-ghfir li ma asrartu wa ma a'lantu, wa ma akhta'tu wa ma 'amadtu, wa ma 'alimtu wa ma jahiltu' (O Allah, protect me from the evil of my own self and grant me firmness upon guidance in my affair. O Allah, forgive me the sins I committed in secret and those I committed openly, those I committed by mistake and those I committed deliberately, those I know and those I am unaware of)." This hadith is sahih (authentic) on the condition of the two Shaykhs (Bukhari and Muslim), but they did not record it.