Incense: Offered by Nadab and Abihu in an Unauthorized Manner
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Leviticus 10:1, 2
Now Aaron’s sons Nadab and Abihu took their censers, put fire in them and added incense, and offered unauthorized fire before the LORD, contrary to His command. / So fire came out from the presence of the LORD and consumed them, and they died in the presence of the LORD.