Numbers 3:1-6

1 These are the descendants of Aharon and Moshe as of the day when ADONAI spoke with Moshe on Mount Sinai.
2 The names of the sons of Aharon are: Nadav the firstborn, Avihu, El'azar and Itamar.
3 These were the names of the sons of Aharon the cohen, whom he anointed and ordained as cohanim.
4 But Nadav and Avihu died in the presence of ADONAI when they offered unauthorized fire before ADONAI in the Sinai Desert, and they had no children; El'azar and Itamar served as cohanim in the presence of Aharon their father.
5 ADONAI said to Moshe,
6 "Summon the tribe of Levi, and assign them to Aharon the cohen, so that they can help him.
Complete Jewish Bible Copyright 1998 by David H. Stern. Published by Jewish New Testament Publications, Inc. All rights reserved. Used by permission.