Revelation 20:2-4

Amplified Bible

² And he overpowered and laid hold of the dragon, that old serpent [of primeval times], who is the devil and Satan, and bound him [securely] for a thousand years (a millennium);^{(A) 3} and the angel hurled him into the abyss, and closed it and sealed it above him [preventing his escape or rescue], so that he would no longer deceive and seduce the nations, until the thousand years were at an end. After these things he must be liberated for a short time.

The Millennial Reign

⁴ And then I saw thrones, and sitting on them were those to whom judgment [that is, the authority to act as judges] was given. And I saw the souls of those who had been beheaded because of their testimony of Jesus and because of the word of God, and those who had refused to worship the beast or his image, and had not accepted his mark on their forehead and on their hand; and they came to life and reigned with Christ for a thousand years.^(B)