Mishkat al-Masabih #1807

Abu Musa al-Ash‘ari reported God’s messenger as saying that every Muslim must give sadaqa. He was asked how this could apply to one who had nothing and replied that he should work with his hands, gaining benefit for himself thereby, and give sadaqa. He was asked what would happen if he were unable to do this or did not do it, and replied that he should help one who was in need and sad. He was asked what he should do if he did not do that and replied that he should enjoin what is good. He was asked what he should do if he did not do that, and replied that he should refrain from evil, for that would be sadaqa for him. (Bukhari and Muslim.)