Numbers 3:41-43

New Revised Standard Version, Anglicised Catholic Edition

⁴¹ But you shall accept the Levites for me—I am the Lord—as substitutes for all the firstborn among the Israelites, and the livestock of the Levites as substitutes for all the firstborn among the livestock of the Israelites. ⁴² So Moses enrolled all the firstborn among the Israelites, as the Lord commanded him. ⁴³ The total enrolment, all the firstborn males from a month old and upwards, counting the number of names, was twenty-two thousand two hundred and seventy-three.