At the conclusion of the Great Tribulation, a transition in power takes place that makes it possible for Jesus to begin his millennial reign on Earth. John tells us, “the beast was captured, and with him the false prophet who worked signs in his presence, by which he deceived those who received the mark of the beast and those who worshiped his image. These two were cast alive into the lake of fire burning with brimstone.” (Revelation 19:20, NKJV). Even though the beast and the false prophet received immediate judgment from God and were punished for their deception of everyone on Earth, John indicated that Satan was only bound with chains and cast in the bottomless pit until the “the thousand years were finished. But after these things he must be released for a little while” (Revelation 20:3, NKJV). Satan’s temporary imprisonment seems to suggest that evil will still exist in the world during the millennium, but it will be restrained by the military force that defeats Antichrist’s political regime (Revelation 19:14, 21). The reason Satan must be loosed at the end of the millennium could be because he is still able to utilize his power until God’s final judgment of mankind begins.
God’s judgment starts in the millennium, but the initial phase seems to be limited to what has just happened during the Great Tribulation. John said, “And I saw thrones, and they sat upon them, and judgment was given unto them: and I saw the souls of them that were beheaded for the witness of Jesus, and for the word of God, and which had not worshipped the beast, neither his image, neither had received the mark upon their foreheads, or in their hands; and they lived and reigned with Christ a thousand years. But the rest of the dead lived not again until the thousand years were finished. This is the first resurrection” (Revelation 20:4-5). It’s possible that the first resurrection only applies to the nation of Israel and the promises that God made specifically to his chosen people. If so, this judgment might be based on the Mosaic Law and could determine whether or not the Jews that took the mark of the beast and worshipped Antichrist will be allowed to inherit the eternal kingdom that was promised to Abraham and his descendants (Genesis 17:8).
According to John’s prophecy, there will be an innumerable amount of people that will join with Satan at the end of the millennium to try and overthrow God’s kingdom (Revelation 20:8). John indicated, “They went up on the breadth of the earth and surrounded the camp of the saints and the beloved city. And fire came down from God out of heaven and devoured them. The devil, who deceived them, was cast into the lake of fire and brimstone where the beast and the false prophet are. And they will be tormented day and night forever and ever” (Revelation 20:9-10, NKJV). The unusual thing about Satan’s final defeat is that he wasn’t allowed to harm anyone when he and his army surrounded the camp of the saints and the city of Jerusalem. It appears that God might have just been using Satan to identify and eliminate all the rebels that were still left on Earth. The fire that came down from heaven was like a holy cleansing agent that was able to completely rid the world of Satan’s evil influence once and for all.
God’s final judgment of mankind was described by Jesus shortly before he was crucified. Jesus said, ““When the Son of Man comes in His glory, and all the holy angels with Him, then He will sit on the throne of His glory. All the nations will be gathered before Him, and He will separate them one from another, as a shepherd divides his sheep from the goats. And He will set the sheep on His right hand, but the goats on the left” (Matthew 25:31-33). The throne of glory Jesus referred to is depicted in Revelation 20:11 as “a great white throne.” John said of this event, “And I saw the dead, small and great, standing before God; and the books were opened: and another book was opened, which is the book of life: and the dead were judged out of those things which were written in the books, according to their works” (Revelation 20:11-12). The Greek word translated dead, nekros refers to a corpse, but it is “the actual spiritual condition of unsaved men” (G3498). Everyone that is not saved or born again will be judged by God according to their works. Jesus said the criterion for judgment would be the kind of treatment shown to the Jewish people (note on Matthew 25:31-46), but John indicated, “whosoever was not found written in the book of life was cast into the lake of fire” (Revelation 20:15).