Numbers 18:14-18

¹⁴Every thing devoted in Israel shall be thine.

¹⁵Whatever openeth the womb of all flesh, which they bring unto the Lord, be it of men or of cattle, shall be thine: nevertheless thou shalt redeem the first-born of man, and the firstling of the unclean cattle shalt thou redeem.

¹⁶And those that are to be redeemed from a month old shalt thou redeem, according to the usual estimation of five shekels of silver, after the shekel of the sanctuary, which is twenty gerahs.

¹⁷But the firstling of an ox, or the firstling of a sheep, or the firstling of a goat, thou shalt not redeem; they are holy: their blood shalt thou sprinkle upon the altar, and their fat shalt thou burn as a fire-offering, for a sweet savor unto the Lord.

¹⁸And their flesh shall be thine: as the breast that is waved and as the right shoulder shall it be thine.