Leviticus 27:26-33

26"But a firstborn of animals, which as a firstborn belongs to the Lord, no man may dedicate; whether ox or sheep, it is the Lord's.

27And if it is an unclean animal, then he shall buy it back at the valuation, and add a fifth to it; or, if it is not redeemed, it shall be sold at the valuation.

28"But no devoted thing that a man devotes to the Lord, of anything that he has, whether man or beast, or of his inherited field, shall be sold or redeemed; every devoted thing is most holy to the Lord.

29No one devoted, who is to be devoted for destruction from mankind, shall be ransomed; he shall surely be put to death.

30"Every tithe of the land, whether of the seed of the land or of the fruit of the trees, is the Lord's; it is holy to the Lord.

31If a man wishes to redeem some of his tithe, he shall add a fifth to it.

32And every tithe of herds and flocks, every tenth animal of all that pass under the herdsman's staff, shall be holy to the Lord.

33One shall not differentiate between good or bad, neither shall he make a substitute for it; and if he does substitute for it, then both it and the substitute shall be holy; it shall not be redeemed."