Nadab and Abihu (Leviticus 9-10)
In chapter 9 Moses instructs Aaron to proceed and offer the first offerings as God's high priest. In verse 15, the offering for the people is a goat. While the animal specified as a sin offering for the congregation in Leviticus 4:14 was a bull, a goat was used for this purpose on some occasions (16:9, 5; Numbers 28-29; 15:22-26; 2 Chronicles 29:20-24; Ezra 6:17; 8:35).
At this inauguration of sacrifices, Aaron pronounces a blessing on Israel (verse 22). The specific wording of the priestly blessing that God commanded to be bestowed upon Israel is given in Numbers 6:23-26. This may be the blessing to which Leviticus 9:22 refers.
In verses 23-24 we see a spectacular event. "The sacrifices were consumed, not by fire ignited by Aaron, but by fire from before the Lord. This is the first of only five times that the Old Testament records fire from God as a sign that a sacrifice was accepted (Judg. 6:21; 1 Kin. 18:38; 1 Chr. 21:26; 2 Chr. 7:1). Since the fire on this altar was never to go out [see Leviticus 6:9, 12-13], all Israel's sacrifices from this time forward would be consumed by fire that originated from God" (Nelson Study Bible, note on 9:24). However, while certainly plausible, it is not absolutely clear that this was the case.
After Aaron's sons are later killed for bringing profane fire before the Lord, Moses explains to Aaron why God has done this and then instructs Aaron's cousins to remove the dead men from the sanctuary. God then commands Aaron and his sons to not drink alcohol before going into the tabernacle of meeting. But the account had only spoken of Nadab and Abihu bringing profane fire and incense before Godso why is this particular instruction regarding intoxicating drink given to Aaron in the midst of what had just happened? Although it is possible that God was simply relating another way that one could show disregard for him during these rituals, the text here may be indicating that the inappropriate use of alcohol had played a role in the two brothers' poor judgment and behavior.
The punishment God inflicted on the two was very severe. We know there are certainly many times where people have "worshiped" God in a way that He does not recognize or appreciate, yet for which He does not strike them down immediately. However, at the time of this account, God was playing a very visible role in the nation of Israel and was actually teaching the people the magnitude of reverence they needed to have for Him: "By those who come near Me I must be regarded as holy; and before all the people I must be glorified" (Leviticus 10:3)it was critical for them to understand.
What Aaron's sons did was not in ignorance, for God had already given clear instructions through Moses on how He was to be regarded. In this situation, Nadab and Abihu's disregard and carelessness could not go uncorrectedit was not only offensive to God, but would have fostered a careless attitude about God's instructions among the people. When God says to regard Him as holy, He means it. The instructive nature of this event was so important that Aaron and his remaining sons were not allowed to show any outward sign of grievancethey were required to maintain their composure and to continue their priestly duties to illustrate the justice and righteousness of God's wrath.
The NIV Study Bible notes regarding the death of Nadab and Abihu: "They are regularly remembered as having died before the Lord and as having had no sons. Their death was tragic and at first seems harsh, but no more so than that of Ananias and Sapphira (Acts 5:1-11). In both cases a new era was being inaugurated.... The new community had to be made aware that it existed for God, not vice versa."
Moses pointing out that the goat of the sin offering (Leviticus 10:16) was not to be burned but eaten by the priests shows that this particular sin offering was not for the whole congregation or priesthood (see Leviticus 4). It is thus a later offering than the one referred to in 9:15. Following the death of his nephews, Moses was rather concerned about making sure everything was being done correctly. In verse 18, he isn't rebuking Aaron's sons for failing to bring the blood into the holy place, but rather pointing out that, because the blood was not brought in, the offering was to be eaten, not burned (see 6:29-30).
Aaron explains that he himself did not eat of the offering because he was afraid God would not accept it. Eating of the sin offering was an act of worship symbolizing satisfaction with God's justice, and Aaron understood the need to be in a proper and reverential frame of mind. Yet he and his sons were sorely grieved and distracted by what had happenedperhaps even unnerved and unhappy with God's judgment for the moment.
"Aaron did not eat of the sacrificial meat because he was afraid of what more God might do. He was not being rebellious, as his dead sons had been in burning the incense. Aaron was arguing that in circumstances such as the one he faced that day, God would prefer the priest to err on the side of caution rather than presumption.... Rebellion arises from a heart that is not right toward God. Moses recognized that Aaron's failure was not rebellion, that his argument had merit, and that Aaron could be forgiven" (Nelson Study Bible, notes on verses 19-20).