Sayyiduna Zayd bin Khalid al-Juhani (may Allah be pleased with him) says that the Messenger of Allah (peace and blessings be upon him) said: "Whoever provides a fasting person with food to break his fast will have the like of his reward, and nothing will be reduced from his reward; and whoever equips a fighter in the path of Allah will have the like of his reward, and nothing will be reduced from his reward."
Hadith Referenceالمعجم الكبير للطبراني / باب الزاي / 5256