Leviticus 10:1-5

1Now Nadab and Abihu, the sons of Aaron, took their respective [ceremonial] censers, put fire in them, placed incense on it and offered strange (unauthorized, unacceptable) fire before the Lord, [an act] which He had not commanded them to do.

2And fire came out from the presence of the Lord and devoured them, and they died before the Lord.

3Then Moses said to Aaron, “This is what the Lord said: ‘I will be treated as holy by those who approach Me, And before all the people I will be honored.’ ” So Aaron, therefore, said nothing.

4Moses called Mishael and Elzaphan, the sons of Uzziel who was Aaron’s uncle, and said to them, “Come here, carry your relatives away from the front of the sanctuary and take them outside the camp.”

5So they came forward and carried them, still in their undertunics, outside the camp, as Moses had said.