Leviticus 27:32-34

³²And as to every tithe of the herd, or of the flock, of whatever passeth under the rod, the tenth shall be holy to Jehovah.

³³He shall not search whether it be good or bad, neither shall he change it; and if he change it at all, then both it and the exchange thereof shall be holy; it shall not be redeemed.

³⁴These are the commandments which Jehovah commanded Moses for the children of Israel upon mount Sinai.