Musnad Ahmad 652:78

Ahmad ibn Abd al-Malik narrated to us, Zuhayr narrated to us, Jabir narrated to us, Abu 'Azib narrated to us, he said: We entered upon al-Nu'man ibn Bashir regarding a testimony, and I heard him say: The Messenger of Allah, may Allah bless him and grant him peace, said—or I heard him say: I heard the Messenger of Allah, may Allah bless him and grant him peace, saying: "Everything is a mistake, except for the sword. And in every mistake, there is a compensation (arsh)."