Musannaf Ibn Abi Shayba 5:917

Ghundar narrated to us, from Shu'bah, from al-Hakam, from al-Hasan ibn Muslim al-Makki, who said: Umar ibn al-Khattab sent a man from Thaqif to collect the charity (sadaqah). He saw him after that day and said: "Do I not see you as having the reward of the warrior in the way of Allah?"