When Jesus returns all unbelievers will die and Satan will be “chained” to the desolate earth (see What Happens at the Second Coming and How Will Satan be Chained?). The “ righteous ” will spend 1000 years (the Millennium) with Christ in Heaven—“And they lived and reigned with Christ for a thousand years” (Revelation 20:4).
John saw “thrones, and they sat on them, and judgment was committed to them”. This passage does not give a comprehensive description of who “they” will be, but mentions “those who had been beheaded for their witness to Jesus”, in other words, the Martyrs, “who lived and reigned with Christ… This is the first resurrection” (Revelation 20:4,5). From 1 Thessalonians 4:16 we learn that this resurrection will include all “the dead in Christ”.
In addition, the righteous who were alive when Jesus comes, who “had not worshiped the beast or his image, and had not received his mark on their foreheads or on their hands” will continue to live during the Millennium.
Verse 4 says that “judgment was given to them”. Although this verse does not give any details, the Apostle Paul informs us that “the saints will judge the world… we shall judge angels” (1 Corinthians 6:2,3). Apparently this is what is meant by the phrase, “they shall be priests of God and of Christ, and shall reign with Him a thousand years” (Revelation 20:6). This does not mean that the saints will judge and decide who will have eternal life; that judgment will have already been made, which is why they will be alive and the “wicked” will be “sleeping” through the Millennium. But the saints will have the opportunity to review the judgments that have been made, so that they can be satisfied with the decisions concerning those who were not granted eternal life.
The Millennial peace will be temporarily broken at the end of the thousand years. “Now when the thousand years have expired, Satan will be released from his prison” (Revelation 20:7). He was “bound” because he was confined to the earth and did not have anyone to tempt, but verse 5 indicates that “the rest of the dead” will be resurrected at the end of the thousand years. They will have been in an unconscious condition, but will come back to life with the same evil propensities that they died with, unaware of the passage of time or the developments of history.
Their ignorance and sinful ambitions will give Satan one last chance to deceive them—“Satan… will go out to deceive the nations which are in the four corners of the earth, Gog and Magog, to gather them together to battle” (v. 7,8).
By this time the saints will have returned to this earth, and Satan and his followers will try to take over the “beloved city” (the New Jerusalem)— “They went up on the breadth of the earth and surrounded the camp of the saints and the beloved city” (v. 9).
At this point the narrative of Revelation 20 gets a little confusing. Verse 9 gives an overview of the fate of the unrighteous— “Fire came down from God out of heaven and devoured them”. Then follows a more detailed explanation which reveals that this is actually the final judgment. A Great White throne will appear and the dead who have been resurrected, “small and great, (will) stand before God, and books (will be) opened. And another book (will be) opened, which is the Book of Life. And the dead (will be) judged according to their works, by the things which were written in the books” v. 12.
All who are found to be hopelessly joined to sin, along with the devil, will be cast into “the lake of fire”. The book of Malachi reveals that “the proud, yes, all who do wickedly will be stubble. And the day which is coming shall burn them up… they shall be ashes” (Malachi 4:1). Even Satan, according to Ezekiel 28:18,19, will be “turned to ashes upon the earth… and shall be no more forever”.
The earth will be transformed by fire—“the heavens will be dissolved, being on fire, and the elements will melt with fervent heat. Nevertheless we, according to His promise, look for new heavens and a new earth in which righteousness dwells” 2 Peter 3:12,13. This is what John saw right after the Millennium: “Now I saw a new heaven and a new earth, for the first heaven and the first earth had passed away” (Revelation 21:1).
For more information about the Millennium and scriptural support see chapter 20 of The Book.
<![if !supportFootnotes]>  <![endif]> The “righteous” are not sinless or perfect; they are only righteous in the sense that God has declared them to be righteous because they believe in Jesus, and they have allowed him to work in their lives through the Holy Spirit to overcome sin.