The first born Israelites were to service the Mishkan but were deemed unworthy and the tribe of Levi replaced them: Bring the Levites forward before the LORD, and the Israelites shall lay their hands on the Levites. As when Moses rested his hands on Joshua, usually the greater person authorizes the lesser person, so why did the Israelites rest their hands on the Levites? This demonstrated that the Israelites fully accepted the newly exalted position of the Levites and they harbored no jealousy toward them. Indeed, to appoint one's replacement is, in such a circumstance, an act of greatness.