Numbers 3:38

Overview - Numbers 3
1	The sons of Aaron.
5	The Levites are given to the priests instead of the first-born;
14	are numbered by their families.
21	The families, number, and charge of the Gershonites;
27	of the Kohathites;
33	of the Merarites.
38	The place and charge of Moses and Aaron.
40	The first-born are freed by the Levites.
44	The overplus are redeemed.

Numbers 3:38  (King James Version)
But those that encamp before the tabernacle toward the east, even before the tabernacle of the congregation eastward, shall be Moses, and Aaron and his sons, keeping the charge of the sanctuary for the charge of the children of Israel; and the stranger that cometh nigh shall be put to death.