Musnad Abu Ya'la al-Mawsili 6:8

Zuhayr narrated to us, Hisham ibn Abd al-Malik narrated to us, Abu 'Awanah narrated to us, from Simak, from Mus'ab ibn Sa'd, from his father, who said: My father took a sword from the spoils of war (al-khums) and brought it to the Prophet, peace and blessings of Allah be upon him, and said: "Grant this to me." But he refused. Then Allah revealed: "They ask you concerning the spoils of war. Say: 'The spoils of war are for Allah and the Messenger.'"