2 Peter 2:4

For if God spared not angels when they sinned, but cast them down to hell, and committed them to pits of darkness, to be reserved unto judgment;

Peter with this verse cited some historical examples of God's judgment and condemnation of the wicked (noting also that the righteous were spared), these being: (1) the example of the sinning angels; (2) the case of Noah and his generation; (3) the example of Sodom and Gomorrah; and (4) the deliverance of Lot. It is an unqualified mystery to this writer why anyone should suppose that Peter found all this in the Book of Enoch, or some other apocryphal writing. Peter received this from the Lord; for he was present when the Lord cited these very things, and in exactly the same order, (Luke 17:25ff), and connecting them, as Peter did here, with developments in the after times. Furthermore, as Paine pointed out:

There is (in Peter's account) an absence of that rather wild and questionable theorizing and intrusion of non-spiritual concept which is evident even to the casual reader of Enoch.[21]

The reason for this is clear. Peter was not inspired by Enoch, but by the Lord Jesus Christ.

Angels, when they sinned ... Very little is known of this; but, if as widely assumed, Satan himself was the leader of the sinning angels, it was through pride that he fell (Ezekiel 28:12ff, and 1 Timothy 3:6); and from this is the deduction that pride was also the sin of the angels, a suggestion not denied by Jude 1:1:6. The point Peter made was that God did not spare them, but condemned them.

Cast them down to hell ... The word here rendered "hell" is "Tartarus," a word not found in any other of the sacred writings.[22] The meaning of the word must therefore be sought in the pagan literature. Strachan said:

In Homer, Hades is the place of confinement of dead men, and Tartarus is the name given to a murky abyss beneath Hades, in which the sins of fallen immortals are punished.[23]

Macknight tells that there were other pagan references to Tartarus as being "in the air."[24] It was natural for Peter, writing to Greeks, to use their word with reference to the state of condemnation of the angels, but without endorsement of any of the pagan traditions about the fallen Titans. It was an "ad hominem" use of the expression here. It would appear that the demons themselves used another of the pagan words for this very place. See Luke 8:31, where is the record that the demons besought Jesus not to send them into the abyss.

Committed them to pits of darkness ... The language here is figurative, darkness symbolizing their separation from God and their existence under his disapproval and condemnation.

To be reserved unto judgment ... The fallen angels are not being punished now, but they are reserved to the day of judgment. The point is that, "If angels that sinned are confined in nether gloom until the judgment, assuredly heretical teachers and their immoral followers should know that `their destruction has not been asleep.'"[25]

[21] Stephen W. Paine, op. cit., p. 995.

[22] James Macknight, op. cit., p. 543.

[23] R. H. Strachan, op. cit., p. 135.

[24] James Macknight, op. cit., p. 544.

[25] Albert E. Barnett, op. cit., p. 190.