Deuteronomy 14:28-29

28At the end of every three years, bring all the tithes of that year’s produce and store it in your towns, 29so that the Levites (who have no allotment or inheritance of their own) and the foreigners, the fatherless and the widows who live in your towns may come and eat and be satisfied, and so that the LORD your God may bless you in all the work of your hands.