Rev20:1 And I saw an angel coming down out of heaven, having the key to the Abyss and holding in his hand a great chain. 2 He seized the dragon, that ancient serpent, who is the devil, or Satan, and bound him for a thousand years. 3 He threw him into the Abyss, and locked and sealed it over him, to keep him from deceiving the nations anymore until the thousand years were endedIn the New Testament, the original Greek word of the Scriptures, pronounced ab-us-sos, describes a deep pit - so deep that it is, in effect, bottomless. I say in effect bottomless because the Scriptures describe the abyss as being on earth, or rather in the earth, and therefore it cannot be deeper from the surface than the earth's radius (surface to center) i.e. about 4,000 miles. Since the Bible refers to the abyss as a place where demons are imprisoned, it would not then be entirely a physical place within the earth anyway, since demons are spirits who can pass through physical barriers. The abyss is logically a spiritual and physical place within the earth. Depending on the version of the Bible, the original Greek word is variously translated as "abyss," "the deep," or "the bottomless pit."
After the antichrist and the false prophet are dispensed with, the fate of satan is prophesied. An angel will bind him and throw him into the Abyss for a thousand years. This is the beginning of the true new millennium. Unlike any event in recorded history, this particular event will change everything as it initiates the thousand year reign of Christ on earth.
The banishment of satan to the depths of the Abyss (which isn’t hell, by the way) for one thousand years is accomplished for a specific purpose, i.e. to keep him from deceiving the nations for that time period. His influence will be removed; his voice will be mute. He will be locked away, in prison if you will, and will be powerless. His prison is locked and sealed with the power and authority of Christ. This task is accomplished by an angel; some opine that the binding is accomplished by Jesus Christ Himself while others take the position that it is merely an angel of the heavenly realm. If the latter is the case, then satan will be overpowered by one who was once his underling.
Satan will go into the Pit or Abyss: Several verses reveal a future judgment that Satan faces. In Isaiah 14:12, "Nevertheless you will be thrust down to Sheol (Greek for "grave"), to the lowest recesses of the Pit. Those who see you will gaze at you, they will ponder over you, saying, 'Is this the man who made the earth tremble, who shook kingdoms, who made the world like a wilderness and overthrew its cities…?'"
The apostle John also saw this future event in a vision from God, Revelation 20:1-3, "Then I saw an angel coming down from heaven, holding the key of the abyss and a great chain in his hand. And he laid hold of the dragon, the serpent of old (the serpent in the Garden of Eden), who is the devil and Satan, and bound him for a thousand years; and he threw him into the abyss, and shut it and sealed it over him, so that he would not deceive the nations any longer, until the thousand years were completed; after these things he must be released for a short time."