Revelation 17:18: And the woman which thou sawest is that great city, which reigneth over the kings of the earth.

Revelation 17:18 has a dualistic meaning that corresponds to the evolving nature of the woman of false religion described throughout Revelation 17.¹ The woman in this verse first sat on the scarlet coloured beast in Revelation 17:3 to represent false religion in the Roman Empire during the first century AD.² At that time she was supported by the great city called Rome.³ That same symbolic woman evolved into the woman arrayed in purple and scarlet colour, and decked with gold and precious stones and pearls in Revelation 17:4 at the time Constantine made apostate Christianity the state religion of the Roman Empire.⁴ The same woman of false religion spiritually matured into the Great Whore⁵ that sits today on many waters.⁶ Today, the woman of false religion is also called Spiritual Babylon⁷ and Modern Babylon.⁸ The wickedness of ancient Rome foreshadows Modern Babylon,⁹ which has now become a metaphorical city that covers the entire world wherever Zion does not exist.¹⁰ The great city of Modern Babylon stands opposite the city of Zion¹¹ and fights against Zion.¹²

The great city of Rome reigned with great wickedness¹³ over the kings of the earth in the ancient Roman Empire until the time of the Reformation.¹⁴ Modern Babylon is the latter-day version of ancient Rome.¹⁵ Today, Modern Babylon increasingly reigns over the symbolic ten kings of the modern nations with the same kind of influence that Rome once had over the kings of the earth in her day of power.¹⁶ Modern Babylon derives its name from the ancient city of Babylon,¹⁷ whose wickedness and worldliness was legendary from the earliest times.¹⁸ The worldliness of Modern Babylon today is the antitype for Rome, which is also an antitype for ancient Babylon.¹⁹

Modern Babylon embodies extreme wickedness²⁰ and all forms of false religion.²¹ The Satanic ideology in Modern Babylon comes from the woman of false religion that has become the Great Whore.²² Her evil influence infects²³ every sector of society²⁴ through the secular instrumentalities of the Second Beast.²⁵ The power of the Second Beast is manifest in secular institutions,²⁶ including those that are educational,²⁷ political,²⁸ and economic.²⁹ These institutions of the Second Beast³⁰ include any persons who accept, practice, or promote Satan's worldly ideology.³¹ The Great Whore of false religion and her earthly institutions‒collectively, Modern Babylon‒will be destroyed at the Second Coming, as described in Revelation 18.³²

And after these things I saw another angel come down from heaven, having great power; and the earth was lightened with his glory. And he cried mightily with a strong voice, saying, Babylon the great is fallen, is fallen.

— Revelation 18:1-2