But the firstborn of cattle, or the firstborn of sheep or the firstborn of goats you shall not redeem; they are holy. Their blood you must splash on the altar and their fat you must burn as an oblation of pleasing aroma to the Lord.
because every firstborn is mine. When I struck down all the firstborn in the land of Egypt, I consecrated to me every firstborn in Israel, human being and beast alike. They belong to me; I am the Lord. Census of the Levites.
You shall consecrate to the Lord, your God, every male firstling born in your herd and in your flock. You shall not work the firstlings of your cattle, nor shear the firstlings of your flock.