Numbers 18:14-19

141Everything banned from secular use in Israel shall be yours.

1523Every firstborn of the womb of all flesh, whether human or animal, which they offer to the Lord, shall be yours; however you must redeem the human firstborn, and the firstborn of unclean animals you shall redeem.

16As to 4their redemption price, from a month old you shall redeem them, by your assessment, five 5shekels in silver by the 6shekel of the sanctuary, which is twenty gerahs.

17But 7the firstborn of an ox, the firstborn of a sheep, or the firstborn of a goat, you shall not redeem; they are holy. 8You shall sprinkle their blood on the altar and offer up their fat in smoke as an offering by fire, for a soothing aroma to the Lord.

18However, their 9meat shall be yours; it shall be yours like the 10breast of a wave offering and like the right thigh.

1911All the offerings of the holy gifts, which the sons of Israel offer to the Lord, I have given to you and your sons and your daughters with you, as a permanent allotment. It is 12a permanent covenant of salt before the Lord to you and your 13descendants with you.”