“‘Surely no man may consecrate a firstborn that already belongs to the Lord as a firstborn among the animals; whether it is an ox or a sheep, it belongs to the Lord.
We also accept responsibility, as is written in the law, for bringing the firstborn of our sons and our cattle and the firstborn of our herds and of our flocks to the temple of our God, to the priests who are ministering in the temple of our God.
If, however, it is among the unclean animals, he may ransom it according to its conversion value and must add one fifth to it, but if it is not redeemed it must be sold according to its conversion value.
But you must not redeem the firstborn of a cow or a sheep or a goat; they are holy. You must splash their blood on the altar and burn their fat for an offering made by fire for a pleasing aroma to the Lord.
because all the firstborn are mine. When I destroyed all the firstborn in the land of Egypt, I set apart for myself all the firstborn in Israel, both man and beast. They belong to me. I am the Lord.”
You must set apart for the Lord your God every firstborn male born to your herds and flocks. You must not work the firstborn of your bulls or shear the firstborn of your flocks.