Leviticus 27:26-31

²⁶Only the firstling of the beasts, which should be the LORD'S firstling, no man shall sanctify it; whether ox, or sheep: it is the LORD'S.

²⁷And if it shall be of an unclean beast, then he shall redeem it , according to thy estimation, and shall add to it a fifth part of it: or if it shall be not redeemed, then it shall be sold according to thy estimation.

²⁸Notwithstanding, no devoted thing that a man shall devote to the LORD of all that he hath, both of man and beast, and of the field of his possession, shall be sold or redeemed: every devoted thing is most holy to the LORD.

²⁹None devoted, which shall be devoted by men, shall be redeemed: but shall surely be put to death.

³⁰And all the tithe of the land, whether of the seed of the land, or of the fruit of the tree, is the LORD'S: it is holy to the LORD.

³¹And if a man will at all redeem aught of his tithes, he shall add to it the fifth part of it.