What Went Wrong?
The punishment seems harsh. One moment, Aaron’s sons are joyously serving the Lord in his tabernacle and the next, Yahweh has consumed them with fire, ending their lives. Assuming that God is just, and certainly not capricious, the only plausible explanation is that Nadab and Abihu were guilty of a truly heinous crime. What went wrong?
The Leviticus narrative describes their crime as that of offering “unholy fire before the Lord, such as he had not commanded them.” (Lev. 10.1) However, as suggested in Matthew Henry’s Commentary and in The Expositor’s Bible Commentary, Aaron’s sons were probably drunk. Both commentaries point to God’s command to Aaron immediately after this incident. Leviticus 10.9 states, “Drink no wine or strong drink, neither you nor your sons, when you enter the tent of meeting, that you may not die.”
It is likely that “unholy fire” was a euphemism pointing the reader to the attitudes of the hearts of Nadab and Abihu. Because they were intoxicated, they were incapable of performing the duties assigned to them with the care and piety required by the Lord. It is not the routine ritual that He requires; it is a contrite heart. This idea reminds me of Cain’s offering not being acceptable and David’s first attempt to bring the Ark of the Covenant to Jerusalem which resulted in the death of Uzzah.
God is a holy God and when we approach him we must approach him with a heart that seeks to honor him and him alone. This is not to suggest that humanity must be perfect before we enter his presence, but it does suggest that we ought not enter his presence with a careless, self-righteous, and proud heart that seeks to use God for our own benefit. We need to approach God with a humble heart and a penitent spirit for that is the offering that pleases God.
King David sums it up best in Psalm 51.17, “My sacrifice, O God, is a broken spirit, a broken and contrite heart you, God, will not despise.”