They said: This incense is an instrument of punishment. It killed Nadav and Avihu, viz. (Leviticus 10:1) "And the sons of Aaron, Nadav and Avihu, took each of them his coal-pan, etc." Therefore, let all of Israel know that it can (also) effect atonement, viz. (Numbers 17:12) "and he put on the incense and he atoned for the people."