1 Chronicles 23:12-14

The four sons of Kohath: Amram, Izhar, Hebron, and Uzziel. The sons of Amram: Aaron and Moses. Aaron was especially ordained to work in the Holy of Holies, to burn incense before GOD, to serve God and bless his Name always. This was a permanent appointment for Aaron and his sons. Moses and his sons were counted in the tribe of Levi.