A book of great debate, Revelation's author, John, makes clear that it is prophecy: a recounting of his symbolic dreams and visions which bring the Old Testament prophets' message to its climax. It is not a secret code about the timing of the end of the world: rather John draws on Old Testament imagery which he expects his readers to look up and understand. The aim is to help believers live through the present day in light of history's final outcome. Chapters 12-22 focus on the spiritual battle behind the world we see, the final judgment and the eventual bringing about of the New Jerusalem. The aim is to present a stark choice to the 7 churches: will they resist the lure of Babylon and follow the Lamb, or follow the beast and suffer its defeat?