“All the firstborn males that are born of your herd and flock you shall dedicate to the Lord your God. You shall do no work with the firstborn of your herd, nor shear the firstborn of your flock.
But the firstborn of a cow, or the firstborn of a sheep, or the firstborn of a goat, you shall not redeem; they are holy. You shall sprinkle their blood on the altar and shall burn their fat as a food offering, with a pleasing aroma to the Lord.
And if it is an unclean animal, then he shall buy it back at the valuation, and add a fifth to it; or, if it is not redeemed, it shall be sold at the valuation.
for all the firstborn are mine. On the day that I struck down all the firstborn in the land of Egypt, I consecrated for my own all the firstborn in Israel, both of man and of beast. They shall be mine: I am the Lord.”
also to bring to the house of our God, to the priests who minister in the house of our God, the firstborn of our sons and of our cattle, as it is written in the Law, and the firstborn of our herds and of our flocks;