Sahih Muslim Book 39, Hadith Number 6765.
Chapter : None would attain salvation because of his deeds but it is through Lord’s Mercy (that he would attain that).
Abu Huraira reported Allah’s Messenger (may peace be upon him) as saying: Observe moderation in deeds (and if it is not possible, try to be near moderation) and understand that none amongst you can attain salvation because of his deeds alone. They said: Allah’s Messenger, not even you? Thereupon he said: Not even I, but that Allah should wrap me in His Mercy and Grace.