Leviticus 27:26-29

26Only the firstling which is offered as firstling to Jehovah among the cattle, that shall no man hallow, whether it be ox or sheep; it is Jehovah's.

27But if it be of an unclean beast, then he shall ransom it according to thy valuation, and shall add a fifth of it thereto; and if it be not redeemed, it shall be sold according to thy valuation.

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

29Nothing devoted, which shall be devoted from among men, shall be ransomed: it shall certainly be put to death.