Leviticus 27:26-33

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.1 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. 28However 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 any of his tithes, he shall add to it the fifth part of it. 32And concerning the tithe of the herd, or of the flock, even of whatever passeth under the rod, the tenth shall be holy to the LORD. 33He shall not search whether it is good or bad, neither shall he change it: and if he shall change it at all, then both it and its substitute shall be holy; it shall not be redeemed.