"The angels who sinned," or fell through sin, are spirits created good by God. Yet they did not stand firm in the good and fell away from God. In Scripture they are called demons (cf. Mt 4:1, 24 and note). The sin through which these once-good angels fell is not precisely indicated in Holy Scripture. One can only conjecture about it, though the very fact of their fall and sin is beyond doubt.
The Lord Himself says of the devil that he did not stand in the truth, and that he is a liar and the father of lies (Jn 8:44; see note). Thus there is an indication of the cause of the devil's fall. He fell away from the truth and turned aside into falsehood. The kingdom of truth was closed to him, and falsehood became his foundation and principle of life. In his inward being there ceased to be, and there is not, truth. Falsehood replaced it in him.
In the holy Apostle Paul there is an indication that the original cause of the devil's fall was the sin of pride (1 Tim 3:6). Through it he rose up against God and, according to the conjectures of certain Fathers of the Church, specifically against the Second Person of the Most Holy Trinity, the Son of God (cf. Heb 1:6).
"Having bound them with chains of infernal gloom": in the Wisdom of Solomon (Wis 17:17; Wis 18:20), when the Egyptian plagues are described, those subjected to these plagues, the lawless, are said to have been bound with indissoluble bonds of darkness. It may be supposed that in the present passage this image served the Apostle to depict the judgment and punishment of the angels who sinned.
Since the chains here are only an image denoting the binding power of gloom, the same is certainly true in the present passage. The gloom itself holds them bound and is, as it were, their chains. Both in this passage and in the Epistle of Jude (v. 6), the word used is gloom, not darkness or deep darkness. In Jude, verse 13, there is the intensified expression, the gloom of darkness.
If the chains are understood here and there not in the proper sense, then the gloom must not be understood only as the darkness of the malice of evil spirits. It must mean real darkness and gloom. The binding, or imprisonment, in which they are held must be understood as actual confinement, a spiritual enclosure in the bonds of gloom.
Yet this imprisonment, or confinement, of evil spirits is not confinement in one definite place. Though they are in Tartarus, they can also be on earth, deceiving men (1 Pet 5:8; Lk 8:31; Acts 5:3; Acts 13:10). In the same way, captives may be free to a certain degree within the place of their captivity.
"Infernal gloom" is an expression that cannot be translated exactly into Russian. In the holy Apostle Peter it is a completely original expression. It is not found in this form either in the Old Testament in the Septuagint or in the other New Testament books. The same is true of the word Tartarus itself.
Among the ancient Greek classical writers, Tartarus is the subterranean place beneath the earth, utterly dark and cold. It is equivalent to the word abyss (Lk 8:31). Hades, however, is generally the dwelling place of departed or dead souls (cf. Lk 16:23 and note). Gehenna is the place of torment for condemned sinners (cf. Mt 5:22 and note).
"He delivered them to be kept for judgment unto punishment": more precisely, He delivered them for judgment unto torment. Since the very time of their fall, the fallen angels have been tormented in their very being. They have fallen away from the source of good and plunged into evil. Yet a final judgment still awaits them in the future, though they were already condemned at their fall and are ceaselessly condemned in their conscience. Final and eternal torment also awaits them, though they are tormented even now.
The judgment means the Last Judgment (Mt 25:41), and the torments are eternal. Murderers and criminals are put in chains and kept in prison until the final judicial sentence is pronounced upon them. So also God, having cast the fallen angels down from heaven, enclosed them in the bonds of gloom. They are outside spiritual light, joy, consolation, and hope. In this state He keeps them for the judgment of the great day, for final punishment in eternal fire.
Whether they dwell in the air (Eph 6:12), or on earth, or in Tartarus, or in heaven (Rev 12:10), they await the future dread Judgment and eternal torment. Whether they tempt men, conquering the impious and being conquered by the righteous, they await this for themselves. They are like a criminal sentenced to death, who expects no mercy for himself. Thus God did not spare even the fallen angels.
THEOSIS