Musnad Ahmad 1101:25

'Abd al-Razzaq narrated to us, Ma'mar narrated to us, from al-Zuhri, from 'Ata' ibn Yazid al-Laythi, from 'Ubayd Allah ibn 'Adi ibn al-Khiyar, that al-Miqdad ibn al-Aswad narrated to him, saying: I said: "O Messenger of Allah, what is your opinion if I and a man differ?" He mentioned the hadith, except that he said: "Shall I kill him or leave him?"