on Jude 1 :6
The angels which kept not their first estate - Την ἑαυτων αρχην Their own principality. The words may be understood of their having invaded the office or dignity of some others, or of their having by some means forfeited their own. This is spoken of those generally termed the fallen angels; but from what they fell, or from what cause or for what crime, we know not. It is generally thought to have been pride; but this is mere conjecture. One thing is certain; the angels who fell must have been in a state of probation, capable of either standing or falling, as Adam was in paradise. They did not continue faithful, though they knew the law on which they stood; they are therefore produced as the second example.
But left their own habitation - This seems to intimate that they had invaded the office and prerogatives of others, and attempted to seize on their place of residence and felicity.
He hath reserved in everlasting chains - That is, in a state of confinement from which they cannot escape.
Under darkness - Alluding probably to those dungeons or dark cells in prisons where the most flagitious culprits were confined.
The judgment of the great day, - The final judgment, when both angels and men shall receive their eternal doom. See on 2 Peter 2:4 (note). In Sohar Exod., fol. 8, c. 32: "Rabbi Isaac asked: Suppose God should punish any of his heavenly family, how would he act? R. Abba answered: He would send them into the flaming river, take away their dominion, and put others in their place." Some suppose that the saints are to occupy the places from which these angels, by transgression, fell.
on Jude 1 :6
And the angels which kept not their first estate - A second case denoting that the wicked would be punished. Compare the notes, 2 Peter 2:4. The word rendered "estate" (ἀρχὴν archēn) is, in the margin, "principality." The word properly means, "beginning, commencement;" and then that which surpasses others, which is "first," etc., in point of rank and honor; or pre-eminence, priority, precedence, princedom. Here it refers to the rank and dignity which the angels had in heaven. That rank or pre-eminence they did not keep, but fell from it. On the word used here, compare Ephesians 1:2; Ephesians 3:10; Colossians 2:10, as applied to angels; 1 Corinthians 15:24; Ephesians 6:12; Colossians 2:15, as applied to demons.
But left their own habitation - To wit, according to the common interpretation, in heaven. The word rendered "habitation" (οἰκητήριον oikētērion) occurs nowhere else in the New Testament. It means here that heaven was their native abode or dwelling-place. They left it by sin; but the expression here would seem possibly to mean that they became "dissatisfied" with their abode, and voluntarily preferred to change it for another. If they did become thus dissatisfied, the cause is wholly unknown, and conjecture is useless. Some of the later Jews supposed that they relinquished heaven out of love for the daughters of men - "Robinson."
He hath reserved in everlasting chains - See the notes, 2 Peter 2:4. Peter says, "chains of darkness;" that is, the darkness encompasses them "as" chains. Jude says that those chains are "everlasting," (δεσμοῖς ἀΐ́δίοις desmois aidios. Compare Romans 1:20, "his eternal power and Godhead." The word does not elsewhere occur. It is an appropriate word to denote that which is eternal; and no one can doubt that if a Greek wished to express that idea, this would be a proper word to use. The sense is, that that deep darkness always endures; there is no intermission; no light; it will exist forever. This passage in itself does not prove that the punishment of the rebel angels will be eternal, but merely that they are kept in a dark prison in which there is no light, and which is to exist for ever, with reference to the final trial. The punishment of the rebel angels after the judgment is represented as an everlasting fire, which has been prepared for them and their followers, Matthew 25:41.
on Jude 1 :6
1:6 And the angels, who kept not their first dignity - Once assigned them under the Son of God. But voluntarily left their own habitation - Then properly their own, by the free gift of God. He reserved - Delivered to be kept. In everlasting chains under darkness - O how unlike their own habitation! When these fallen angels came out of the hands of God, they were holy; else God made that which was evil: and being holy, they were beloved of God; else he hated the image of his own spotless purity. But now he loves them no more; they are doomed to endless destruction. (for if he loved them still, he would love what is sinful:) and both his former love, and his present righteous and eternal displeasure towards the same work of his own hands, are because he changeth not; because he invariably loveth righteousness, and hateth iniquity. 2Pet 2:4.