Leviticus 27:26-28

Evangelical Heritage Version

²⁶ However, no one may dedicate a firstborn from the livestock that has already been designated for the Lord as a firstborn, whether it is a head of cattle or a sheep or a goat. It already belongs to the Lord. ²⁷ But if it is one of the unclean livestock, he may buy it back at its set value plus one-fifth. If it is not redeemed, it may be sold at its set value.

²⁸ However, if anyone devotes anything that belongs to him to the Lord unconditionally, whether it is a human being or livestock or any part of his landholding, it may not be sold and may not be redeemed. Everything devoted unconditionally is most holy to the Lord.