And Nadab and Abihu, the sons of Aaron, took either of them his censer, and put fire therein, and put incense thereon, and offered {a} strange fire before the LORD, which he commanded them not.

(a) Not taken from the altar, which was sent from heaven, and endured till the captivity of Babylon.

Wesley's Notes

10:1 Strange fire - Fire so called, because not taken from the altar, as it ought, but from some common fire. Before the Lord - Upon the altar of incense. Which he commanded not - Not commanding may be here put for forbidding, as it is, Jer 32:35. Now as this was forbidden implicitly; Lev 6:12, especially when God himself made a comment upon that text, and by sending fire from heaven declared of what fire he there spake; so it is more than probable it was forbidden expressly, though that be not here mentioned, nor was it necessary it should be.

Scofield Reference Notes

[1] fire

Strange fire. Fire "from before the Lord" had kindled upon the altar of burnt-offering the fire which the care of the priests was to keep burning Lev 6:12. No commandment had yet been given Lev 16:12 how the incense should be kindled. The sin of Nadab and Abihu was in acting in the things of God without seeking the mind of God. It was "will worship" Col 2:23 which often has a "show of wisdom and humility." It typifies any use of carnal means to kindle the fire of devotion and praise.

Margin Nadab

Na-dab, 'liberal.'

Margin Abihu

A-bi-hu, 'God is father.'

Jamieson-Fausset-Brown Bible Commentary

CHAPTER 10

Le 10:1-20. Nadab and Abihu Burnt.

1. the sons of Aaron, &c.-If this incident occurred at the solemn period of the consecrating and dedicating the altar, these young men assumed an office which had been committed to Moses; or if it were some time after, it was an encroachment on duties which devolved on their father alone as the high priest. But the offense was of a far more aggravated nature than such a mere informality would imply. It consisted not only in their venturing unauthorized to perform the incense service-the highest and most solemn of the priestly offices-not only in their engaging together in a work which was the duty only of one, but in their presuming to intrude into the holy of holies, to which access was denied to all but the high priest alone. In this respect, "they offered strange fire before the Lord"; they were guilty of a presumptuous and unwarranted intrusion into a sacred office which did not belong to them. But their offense was more aggravated still; for instead of taking the fire which was put into their censers from the brazen altar, they seem to have been content with common fire and thus perpetrated an act which, considering the descent of the miraculous fire they had so recently witnessed and the solemn obligation under which they were laid to make use of that which was specially appropriated to the service of the altars, they betrayed a carelessness, an irreverence, a want of faith, most surprising and lamentable. A precedent of such evil tendency was dangerous, and it was imperatively necessary, therefore, as well for the priests themselves as for the sacred things, that a marked expression of the divine displeasure should be given for doing that which "God commanded them not."

Matthew Henry's Concise Commentary

10:1,2 Next to Moses and Aaron, none were more likely to be honourable in Israel than Nadab and Abihu. There is reason to think that they were puffed up with pride, and that they were heated with wine. While the people were prostrate before the Lord, adoring his presence and glory, they rushed into the tabernacle to burn incense, though not at the appointed time; both together, instead of one alone, and with fire not taken from the altar. If it had been done through ignorance, they had been allowed to bring a sin-offering. But the soul that doeth presumptuously, and in contempt of God's majesty and justice, that soul shall be cut off. The wages of sin is death. They died in the very act of their sin. The sin and punishment of these priests showed the imperfection of that priesthood from the very beginning, and that it could not shelter any from the fire of God's wrath, otherwise than as it was typical of Christ's priesthood.