Numbers 3:38-40

Revised Standard Version Catholic Edition

³⁸ And those to encamp before the tabernacle on the east, before the tent of meeting toward the sunrise, were Moses and Aaron and his sons, having charge of the rites within the sanctuary, whatever had to be done for the people of Israel; and any one else who came near was to be put to death. ³⁹ All who were numbered of the Levites, whom Moses and Aaron numbered at the commandment of the Lord, by families, all the males from a month old and upward, were twenty-two thousand.

The Redemption of the Firstborn

⁴⁰ And the Lord said to Moses, “Number all the first-born males of the people of Israel, from a month old and upward, taking their number by names.