Leviticus 27:26-29

26Only the firstling among beasts, which is made a firstling to Jehovah, no man shall sanctify it; whether it be ox or sheep, it is Jehovah’s. 27And if it be of an unclean beast, then he shall ransom it according to thine estimation, and shall add unto it the fifth part thereof: or if it be not redeemed, then it shall be sold according to thy estimation.

28Notwithstanding, no devoted thing, that a man shall devote unto Jehovah of all that he hath, whether of man or beast, or of the field of his possession, shall be sold or redeemed: every devoted thing is most holy unto Jehovah. 29No one devoted, that shall be devoted from among men, shall be ransomed; he shall surely be put to death.