Musnad Abu Ya'la al-Mawsili 6:41

Abu Khaythama narrated to us, Waki' narrated to us, from Isra'il, from Simak, from Mus'ab bin Sa'd, from his father, who said: I obtained a sword on the day of Badr, and it pleased me. So I said: "O Messenger of Allah, grant it to me." Then was revealed: "They ask you concerning the spoils of war. Say: 'The spoils of war are for Allah and the Messenger.'"