Sayyiduna Abu Musa (may Allah be pleased with him) narrates from the Prophet (peace and blessings be upon him) that he (peace and blessings be upon him) said: "Feed the hungry, free the captive, and visit the sick." Sufyan says that al-'ani means captives.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجزية / 18827