Revelation 20:1-6 New Revised Standard Version (NRSV)
The Thousand Years
20 Then I saw an angel coming down from heaven, holding in his hand the key to the bottomless pit and a great chain. 2 He seized the dragon, that ancient serpent, who is the Devil and Satan, and bound him for a thousand years, 3 and threw him into the pit, and locked and sealed it over him, so that he would deceive the nations no more, until the thousand years were ended. After that he must be let out for a little while.
4 Then I saw thrones, and those seated on them were given authority to judge. I also saw the souls of those who had been beheaded for their testimony to Jesus[a] and for the word of God. They had not worshiped the beast or its image and had not received its mark on their foreheads or their hands. They came to life and reigned with Christ a thousand years. 5 (The rest of the dead did not come to life until the thousand years were ended.) This is the first resurrection. 6 Blessed and holy are those who share in the first resurrection. Over these the second death has no power, but they will be priests of God and of Christ, and they will reign with him a thousand years.