Korach, from the Tribe of Levi and a cousin of Moshe and Aaron, decided that being part of the Levitical priesthood and ministering in the Mishkan was not enough of an honor. He wanted to be a high priest like Aaron. He wanted a democracy where the majority rules rather than a theocracy governed by those Elohim chooses. So he gathered a group of men, leaders of the community, and in their sin of arrogance and pride, they rebelled against Moshe.