Revelation 20:1-3 (NIV) And I saw an angel coming down out of heaven, having the key to the Abyss and holding in his hand a great chain. He seized the dragon, that ancient serpent, who is the devil, or Satan, and bound him for a thousand years. 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 ended. After that, he must be set free for a short time.
Zechariah 14:8-9 (NIV) On that day living water will flow out from Jerusalem, half of it east to the Dead Sea and half of it west to the Mediterranean Sea, in summer and in winter. The Lord will be king over the whole earth. On that day there will be one Lord, and his name the only name.
Revelation 20:7-10 (NIV) When the thousand years are over, Satan will be released from his prison and will go out to deceive the nations in the four corners of the earth - Gog and Magog - and to gather them for battle. In number they are like the sand on the seashore. They marched across the breadth of the earth and surrounded the camp of God's people, the city he loves. But fire came down from heaven and devoured them. And the devil, who deceived them, was thrown into the lake of burning sulfur, where the beast and the false prophet had been thrown. They will be tormented day and night for ever and ever.
What is the Millennium? It is a period of 1,000 years when Jesus will physically reign on earth in the city of Jerusalem. He “will be the king over the whole earth.” Remember, World War III just ended and the planet is no longer inhabitable. The earth has been knocked off its axis (Isaiah 24:20) and radiation has destroyed the ecosystem. But Jesus does not reign over a desolate, lifeless planet. He will restore its beauty and “On that day living water will flow out from Jerusalem, half of it east to the Dead Sea and half of it west to the Mediterranean Sea, in summer and in winter.” And those who survived World War III will get to live with Christ on earth! Life will continue. Babies will be born. Families will enjoy time together. Friendships will be made. The cycle of life will continue.
But, at the end of the 1,000-year period Satan will be released from his prison. He will use his freedom to “deceive the nations in the four corners of the earth.” His army will march on Jerusalem, but they will be quickly dispatched by fire that comes “down from heaven.” At this point Satan will be “thrown into the lake of burning sulfur” along with the beast and the false prophet where “they will be tormented day and night for ever and ever.” Now that Satan has been dealt with Christ can turn his attention toward eternity.
