Deuteronomy 26:12-13

12Every third year you must keep safe a tenth part of all your crops. In the third year, you must give that tithe to the Levites, the foreigners who live among you, widows and the children who have no family. Then everyone who lives in your towns can eat all the food that they need.

13Then you can say to the Lord your God, ‘None of the tithe that belongs to you remains in my house. I have done what you commanded me to do. I have given it to the Levites, foreigners, widows and the children who have no family. I have not forgotten to obey your commands.