In summary of the chapters 17-19, the beast has devoured Babylon as ordained by God, Jesus has come from heaven with His spiritual armies to destroy the beast and the false prophet, casting them into the lake of fire. Now Jesus has satan bound for 1000 years so he cannot deceive the nations.
I confess I vacillate on my understanding of the 1000 yer reign of Christ, the reign of the saints, and the final binding, then loosening of Satan after the 1000 years. Let us decode this mystery that has given rise to numerous theories from Augustine to Wesley to modern prophets.
Satan is finally defeated and cast into the lake of fire. The great white throne judgment comes against all those not written in the book of life This is a great comfort to all of us who are in the book of life. We need to celebrate this victory and hold fast to it in our times of persecution.