Korah the son of Izhar, a Levite of the family of Kohath, led a revolt with Dathan and Abiram of Reuben and 250 princes of the congregation. Their charge sounded spiritual: All the congregation are holy, everyone of them, and Yahweh is among them. Why do you lift yourselves up? Moses answered, In the morning, Yahweh will show who are his, and who is holy. He exposed their real aim: Do you seek the priesthood also? Their grumbling against Aaron was really against Yahweh.
Dathan and Abiram refused to come and accused Moses of bringing them out of a land flowing with milk and honey, the very words used of Canaan. Moses declared that if the ground opened, the people would know Yahweh had sent him. The earth opened its mouth and swallowed them with their households, and fire consumed the 250 offering incense. Their bronze censers became a covering for the altar, a sign that only Aaron's offspring were to burn incense. Numbers 26:11 later notes that the sons of Korah did not die, and some of their descendants are named in the titles of several Psalms.
The next day the whole congregation murmured, You have killed Yahweh's people. Wrath went out and a plague began. Moses sent Aaron with fire from the altar and incense. Aaron ran into the middle of the assembly, made atonement, and stood between the dead and the living; and the plague was stayed. Hebrews 7:25 says Jesus always lives to make intercession for those who come to God. Like Aaron, but far greater, He stands between us and death.