Numbers 18:15 BBE

¹³  The earliest produce from their land which they take to the Lord is to be yours; everyone in your house who is clean may have it for his food.

¹⁴  Everything given by oath to the Lord in Israel is to be yours.

¹⁵  The first birth of every living thing which is offered to the Lord, of man or beast, is to be yours; but for the first sons of man payment is to be made, and for the first young of unclean beasts.

¹⁶  Payment is to be made for these when they are a month old, at the value fixed by you, a price of five shekels by the scale of the holy place, that is, twenty gerahs to the shekel.

¹⁷  But no such payment may be made for the first birth of an ox or a sheep or a goat; these are holy: their blood is to be dropped on the altar, and their fat burned for an offering made by fire, a sweet smell to the Lord.