Moses did not identify Nadab and Abihu's exact offense in the text. However the "strange fire"seems most likely to have been an incense offering presented apart from God's command. It may have involved assuming the role of the high priest (cf. Heb. 5:4) or offering incense at a time or in a way contrary to God's prescription.90The incident took place on the eighth day of the priests' inauguration (ch. 9; cf. 10:12, 16). Perhaps Nadab and Abihu wanted to add to the festivities by offering an additional incense offering. Nevertheless their action constituted disobedience to God's word regardless of how good its ends might have seemed to them.
This incident should warn modern readers against worshipping God in ways that we prefer because they make us feel "good."We must be careful about worship that is designed to produce effects in the worshippers rather than honoring God. Some forms of contemporary worship may reflect the selfish spirits of Nadab and Abihu.
The same fire that had sanctified Aaron's service brought destruction on Nadab and Abihu because they had not sanctified God (v. 2; cf. Exod. 24:17; Num. 11:1; 16:35; Deut. 5:22; 1 Sam. 15:22; 2 Kings 1:10, 12; Heb. 12:29). Previously it had fallen only after all the sacrifices had been offered, but now it fell instantly. Then it signified God's blessing, but now it manifested His judgment. Then the people rejoiced, but now they were silent.
"Just as the fire that came from before the LORD' had been a sign of God's approval of the dedication of the tabernacle and the priests in the previous chapter (9:24), so also the fire that came from before the LORD' in this chapter (10:2) was a sign of God's disapproval. The writer's clear purpose in putting these two narratives together is to show the importance that God attached to obeying his commands."91
Moses explained God's judgment to Aaron (v. 3). Aaron did not reply because he accepted the righteousness of God's action in judging his sons' sin.
"If we reflect how holy a thing God's worship is, the enormity of the punishment will by no means offend us. Besides, it was necessary that their religion should be sanctioned at its very commencement; for if God had suffered the sons of Aaron to transgress with impunity, they would have afterwards carelessly neglected the whole law. This, therefore, was the reason for such great severity, that the priests should anxiously watch against all profanation."92
The fire had not consumed Nadab and Abihu but simply killed them. Aaron was not to demonstrate any dissatisfaction with God's judgment (vv. 4-7). God permitted the people to mourn because of the loss the nation experienced in the death of these priests and so they would remember His punishment a long time. The anointing oil symbolized the Spirit of God who gives life. For this oil to have any contact with death was inappropriate.
Eleazar and Ithamar replaced their older brothers, Nadab and Abihu, in a way similar to the way Judah and Levi replaced their older brothers, Reuben and Simeon (Gen. 49:2-7). In both families, Jacob's and Aaron's, the sins of the firstborn and secondborn resulted in God passing over them for blessing. They disqualified themselves from some of the inheritance that could have been theirs had they remained faithful.
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