Numbers 3:4

1 Now this is the history of the generations of Aaron and Moses in the day that Yahweh spoke with Moses in Mount Sinai.

2 These are the names of the sons of Aaron: Nadab the firstborn, and Abihu, Eleazar, and Ithamar.

3 These are the names of the sons of Aaron, the priests who were anointed, whom he consecrated to minister in the priest`s office.

4 Nadab and Abihu died before Yahweh, when they offered strange fire before Yahweh, in the wilderness of Sinai, and they had no children; and Eleazar and Ithamar ministered in the priest`s office in the presence of Aaron their father.

5 Yahweh spoke to Moses, saying,

6 Bring the tribe of Levi near, and set them before Aaron the priest, that they may minister to him.

7 They shall keep his charge, and the charge of the whole congregation before the tent of meeting, to do the service of the tent.