Musnad Ahmad 1:53

Muhammad ibn Ja‘far narrated to us, Shu‘bah narrated to us, from Tawbah al-‘Anbari, who said: I heard Abu Siwar al-Qadi saying: From Abu Barzah al-Aslami, who said: A man spoke harshly to Abu Bakr al-Siddiq. Abu Barzah said: "Shall I strike his neck?" He (Abu Bakr) rebuked him and said: "It is not for anyone after the Messenger of Allah, may Allah bless him and grant him peace."