"And I saw an angel descending from heaven, having the key of the abyss and a great chain in his hand. And he seized the dragon, the old serpent, who is the Devil, and Satan, and bound him a thousand years, and cast him into the abyss, and shut him up, and set a seal over him, that he should deceive the nations no more, till the thousand years were completed; and after that, he must be loosed a short time." Rev. 20:1-3.
The angel descending from heaven, must be a representative of his own order; for at this epoch there are no other orders of beings for him to be a representative of. He therefore symbolizes the angels who are commissioned to "gather out of his kingdom all things that offend," Matt. 13:41.
The "key," "pit," and "chain," symbolize the instruments of restraint and confinement to which Satan is to be subjected; and his being bound and confined symbolize his restraint.
The "Dragon" is expressly called "that old serpent, which is the Devil and Satan." With the appendages of heads and horns--symbols of political sovereignty--he is used in Rev. 12:3, as a symbol of the Roman civil power, under Pagan rule; and in verse 7, when divested of political insignia, of the pagan hierarchy. But now, as the beast, another symbol of Roman civil rule, has been cast into "the lake of fire and brimstone," and the "remnant" are "slain with the sword" (19:21), there are no analogous powers remaining on earth for him to be a representative of, and consequently he is here represented as a symbol of himself.
Of his identity there can be no question: He is "that Old Serpent," who, being "more subtle than any beast of the field which the Lord God had made" (Gen. 3:1), "beguiled Eve through his subtlety," 2 Cor. 11:3. He is also the Devil, by whom our Saviour was tempted in the wilderness, (Matt. 4:1-12); and the Satan, whose working is "with all power and signs and lying wonders," 2 Thess. 2:9. He is our adversary the devil, who, "as a roaring lion, walketh about seeking whom he may devour," (1 Pet. 5:8); and against whom we are to guard continually, "lest Satan should get an advantage of us," 2 Cor. 2:11.
Coëval with the fall, the promise was given that his head should in due time be bruised, and he is not ignorant of his doom; for when the legion saw the Saviour about to dispossess them of the two men among the tombs, they recognized him as "the Son of God," and cried, "Art thou come hither to torment us before _the time_?" (Matt. 8:29); "and they besought him, that he would not command them to go out into the _deep_,"--the _pit_, or _abyss_, Luke 8:31. The epoch when he should be there confined, is also shown by Isaiah to be when "the Lord cometh out of his place to punish the inhabitants of the earth for their iniquity," when "the earth also shall disclose her blood, and no more cover her slain," Isa. 26:21. For "in that day the Lord with his sore and great and strong sword shall punish leviathan [the dragon], the piercing serpent, even leviathan that crooked serpent," _Ib._ 27:1. This synchronizes with the slaying of the remnant with the sword, when Satan is bound and cast into the _abyss_, to continue there a thousand years.