Musnad Ahmad 32:1277

'Abd al-Samad narrated to us, 'Abdullah—meaning Ibn Abi Bakr al-Muzani—narrated to us, 'Ata' ibn Abi Maymunah narrated to us, and he said: I do not know it except from Anas, who said: "No matter involving retaliation (qisas) was ever raised to the Messenger of Allah, may Allah bless him and grant him peace, but that he commanded pardon in it."