Musannaf Ibn Abi Shayba 36:125

'Abd al-Rahim ibn Sulayman narrated to us, from Mis'ar, from Abu 'Awn, from Abu Salih al-Hanafi, from 'Ali, who said: It was said to Abu Bakr al-Siddiq and 'Ali on the day of Badr: "With one of you is Jibril, and with the other is Mika'il." And Israfil is a mighty angel who witnesses the fighting or stands in the ranks.