Leviticus 27:23-27

then the priest shall calculate for him the amount of your assessment up to the year of jubilee; and he shall on that day give your assessment as holy to the Lord.

In the year of jubilee the field shall return to the one from whom he bought it, to whom the possession of the land belongs.

Every assessment of yours, moreover, shall be by the shekel of the sanctuary. The shekel shall be twenty gerahs.

‘However, a firstborn among animals, which as a firstborn belongs to the Lord, no one may consecrate; whether ox or sheep, it is the Lord’s.

But if it is among the unclean animals, then he shall redeem it according to your assessment and add to it a fifth of it; and if it is not redeemed, then it shall be sold according to your assessment.