Leviticus 27:9-13

9“If the vow involves one of the animals that may be brought as an offering to the Lord, any of these he gives to the Lord will be holy.

10He may not replace it or make a substitution for it, either good for bad, or bad for good. But if he does substitute one animal for another, both that animal and its substitute will be holy.

11“If the vow involves any of the unclean animals that may not be brought as an offering to the Lord, the animal must be presented before the priest.

12The priest will set its value, whether high or low; the price will be set as the priest makes the assessment for you.

13If the one who brought it decides to redeem it, he must add a fifth to the assessed value.