Numbers 16:10

And He hath brought thee (the tribe of Levi) near to Him, and all thy brethren, the sons of Levi, with thee; and seek ye the priesthood also? The Levites even now held a higher position in the congregation than the other tribes, and their desire to have all Israelites recognized as priests was nothing but sham and pretense, their real aim being the office of the priesthood for themselves.