Numbers 16:46-48

46Then Moses said to Aaron, “Take the censer, put into it fire from the altar and put in incense. Get going and hurry to the assembly and make atonement for them, because wrath has come out from Adonai and the plague has started.”

47Aaron did just as Moses had said, and ran into the middle of the assembly. Behold, the plague had already started among the people. But he offered the incense and made atonement for the people.

48He stood between the dead and the living and the plague stopped.