Numbers 16:40

40to be a reminder to the people of Israel, so athat no outsider, who is not of the descendants of Aaron, should draw near to burn incense before the Lord, lest he become like Korah and his company—as the Lord said to him through Moses.

Numbers 16:46-48

46And Moses said to Aaron, “Take your censer, and put fire on it from off the altar and lay incense on it and carry it quickly to the congregation and make atonement for them, for bwrath has gone out from the Lord; the plague has begun.” 47So Aaron took it as Moses said and ran into the midst of the assembly. And behold, the plague had already begun among the people. And he put on the incense and made atonement for the people. 48And he stood between the dead and the living, and cthe plague was stopped.

Numbers 18:7

7And dyou and your sons with you shall guard your priesthood for all that concerns the altar and ethat is within the veil; and you shall serve. I give your priesthood as a gift,
Hebrew service of gift
and gany outsider who comes near shall be put to death.”

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