"For all the firstborn are Mine; on the day that I struck down all the firstborn in the land of Egypt, I sanctified to Myself all the firstborn in Israel, from man to beast. They shall be Mine; I am the LORD."
"You shall take the Levites for Me, I am the LORD, instead of all the firstborn among the sons of Israel, and the cattle of the Levites instead of all the firstborn among the cattle of the sons of Israel."
"Every first issue of the womb of all flesh, whether man or animal, which they offer to the LORD, shall be yours; nevertheless the firstborn of man you shall surely redeem, and the firstborn of unclean animals you shall redeem.
"From the sons of Israel's half, you shall take one drawn out of every fifty of the persons, of the cattle, of the donkeys and of the sheep, from all the animals, and give them to the Levites who keep charge of the tabernacle of the LORD."
and from the sons of Israel's half, Moses took one drawn out of every fifty, both of man and of animals, and gave them to the Levites, who kept charge of the tabernacle of the LORD, just as the LORD had commanded Moses.