Leviticus 10:1
And Nadab and Abihu, the sons of Aaron, took either of them his censer, and put fire therein, and put incense thereon, and offered strange fire before the LORD, which he commanded them not.
And Nadab and Abihu, the sons of Aaron,.... His two eldest sons, as seems from Exodus 6:23:
took either of them his censer; a vessel in which coals of fire were put, and incense upon them, and burnt it, and so it follows:
and put fire therein, and put incense thereon; which, as Aben Ezra says, was on the eighth day, that is, of their consecration, the day after their consecration was completely finished, and the same day that Aaron had offered the offerings for himself and for the people, see Leviticus 9:1:
and offered strange fire before the LORD; upon the golden altar of incense, which stood in the holy place right against the vail, within which were the ark, mercy seat, and cherubim, the symbol and seat of the divine Majesty: this fire was not that which came down from heaven, and consumed the sacrifice, as related at the end of the preceding chapter Leviticus 9:24, but common fire, and therefore called strange; it was not taken off of the altar of burnt offering, as it ought to have been, but, as the Targum of Jonathan, from under the trivets, skillets, or pots, such as the flesh of peace offerings were boiled in, in the tabernacle;
which he commanded not; yea, forbid, by sending fire from heaven, and ordering coals of fire for the incense to be taken off of the altar of burnt offering; and this, as Aben Ezra observes, they did of their own mind, and not by order. It does not appear that they had any command to offer incense at all at present, this belonged to Aaron, and not to them as yet; but without any instruction and direction they rushed into the holy place with their censers, and offered incense, even both of them, when only one priest was to offer at a time, when it was to be offered, and this they also did with strange fire. This may be an emblem of dissembled love, when a man performs religious duties, prays to God, or praises him without any cordial affection to him, or obeys commands not from love, but selfish views; or of an ignorant, false, and misguided zeal, a zeal not according to knowledge, superstitious and hypocritical; or of false and strange doctrines, such as are not of God, nor agree with the voice of Christ, and are foreign to the Scriptures; or of human ordinances, and the inventions of men, and of everything that man brings of his own, in order to obtain eternal life and salvation.