Musnad Ahmad 28:148

Ishaq ibn Isa narrated to us, Layth narrated to us, Haywah—meaning Ibn Shurayh—narrated to me, from Ibn Shafi al-Asbahi, from his father, from Abdullah ibn Amr, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "For the warrior is his reward, and for the one who provides the means (for the warrior) is his reward and the reward of the warrior."