Sahih Muslim
The Book Pertaining to the Excellent Qualities of the Holy Prophet (may Peace be upon them) and His Companions (Kitab Al-Fadail)
Book Number: 030 / Hadith Number: 5720
Anas b. Malik reported: I served the Messenger of Allah (may peace be upon him) for ten years, and, by Allah, he never said to me any harsh word, and he never said to me about a thing as to why I had done that and as to why I had not done that. Abu Rabi' has made this addition (in this narration):" The work which a servant should do." There is no mention of his words" By Allah".