Numbers 3:38-40

American Standard Version

³⁸ And those that encamp before the tabernacle eastward, before the tent of meeting toward the sunrising, shall be Moses, and Aaron and his sons, keeping the charge of the sanctuary ^[a]for the charge of the children of Israel; and the stranger that cometh nigh shall be put to death. ³⁹ All that were numbered of the Levites, whom Moses and Aaron numbered at the commandment of Jehovah, by their families, all the males from a month old and upward, were twenty and two thousand.

⁴⁰ And Jehovah said unto Moses, Number all the first-born males of the children of Israel from a month old and upward, and take the number of their names.