Numbers 18:26

“And you shall exact a levy for Yahweh from the men of war who went out to battle, one in five hundred of the persons and of the cattle and of the donkeys and of the sheep;

And the priest, the son of Aaron, shall be with the Levites when the Levites receive tithes, and the Levites shall bring up the tenth of the tithes to the house of our God, to the chambers of the storehouse.

And those indeed of the sons of Levi, who receive the priest’s office, have a commandment in the Law to collect a tenth from the people, that is, from their brothers, although these are descended from Abraham.