Leviticus 27:10-12

New King James Version

¹⁰ He shall not substitute it or exchange it, good for bad or bad for good; and if he at all exchanges animal for animal, then both it and the one exchanged for it shall be ^(A)holy. ¹¹ If it is an unclean animal which they do not offer as a sacrifice to the Lord, then he shall present the animal before the priest; ¹² and the priest shall set a value for it, whether it is good or bad; as you, the priest, value it, so it shall be.