Leviticus 27:30-33

“A tenth of the land’s produce, whether grain from the ground or fruit from the trees, is GOD’s. It is holy to GOD. If a man buys back any of the tenth he has given, he must add twenty percent to it. A tenth of the entire herd and flock, every tenth animal that passes under the shepherd’s rod, is holy to GOD. He is not permitted to pick out the good from the bad or make a substitution. If he dishonestly makes a substitution, both animals, the original and the substitute, become the possession of the Sanctuary and cannot be redeemed.”