Then Moses said to Aaron, “Take your censer and put incense in it, along with burning coals from the altar, and hurry to the assembly to make atonement for them. Wrath has come out from the LORD; the plague has started.”
So Aaron did as Moses said, and ran into the midst of the assembly. The plague had already started among the people, but Aaron offered the incense and made atonement for them.
He stood between the living and the dead, and the plague stopped.