Aaron's sons, Nadab and Abihu, set light to their incense burners using ordinary fire and put in incense, and in this way offered forbidden fire in the Lord's presence, something he had not authorized.
Then he told Korah and all those with him, “In the morning the Lord is going to make it clear who is his and who is holy, and allow that person to approach him. He will only allow whoever he chooses to approach him.
and tomorrow put incense in them and set it on fire in the presence of the Lord. Then the man the Lord chooses is the one who is holy. It is you Levites who are taking too much power for yourselves!”