Leviticus 27:8-10

Amplified Bible, Classic Edition

⁸ But if the man is too poor to pay your valuation, then he shall be set before the priest, and the priest shall value him; according to the ability of him who vowed shall the priest value him.

⁹ If it is a beast of which men offer an offering to the Lord, all that any man gives of such to the Lord shall be holy.

¹⁰ He shall not replace it or exchange it, a good for a bad, or a bad for a good; and if he makes any exchange of a beast for a beast, then both the original offering and that exchanged for it shall be holy.