Revelation tells us about the unfolding story of God's grace and Christ's sacrifice so that we can be forgiven and know how to love a fallen world. Christ's resurrection is the proof and pledge that God intends to make all things new.
We are in the final part of the book of Revelation that unfolds The Day of Lord a climactic and final judgment from which God rescues his people. In Revelation 17 we have heard final judgment decreed for all evil. Revelation 18 continues that scene with the series of laments over the fall of Babylon.
Revelation 17 continues the theme of Gods justice enacted against those who oppose him and seek to destroy his people. Chapters 17-18 are about the judgment of Babylon, depicted as a prostitute who rides a scarlet Beast Satan himself.