مسند أحمد

It was narrated from Abu Barzah al-Aslami that he said: We were with Abu Bakr as-Siddeeq when he was conducting some business of caliphate and he got very angry with one of the Muslims. When I saw that I said: O Khaleefah of the Messenger of Allah, shall I strike his neck? When I mentioned killing him, he changed the subject completely, When we parted, Abu Bakr as Siddeeq sent word to me after that and said: O Abu Barzah, what did you say? I said: I have forgotten what I said; remind me. He said: Don't you remember what you said? I said: No, by Allah. He said: Do you remember, when you saw me get angry with that man, you said: Shall I strike his neck, O khaleefah of the Messenger of Allah? Don't you remember that? would you really have done that? I said: Yes, by Allah. If you order me to do it now, I will do it. He said: Woe to you! By Allah, that is not for anyone after Muhammad (ﷺ).