In Revelation 17 the Lord had shown John a vision of a woman with this name on her forehead: Babylon the great, mother of prostitutes and of earth’s abominations
(Revelation 17:5). Through this vision the Lord showed John how the great and the mighty of the world work together under the direction of a single operating principle to destroy the gospel of Jesus Christ and thus also his church, a reality characterizing the new dispensation. Gloriously, however, that effort is ultimately futile because Christ Jesus is victorious (Revelation 17:14, Revelation 17:17). In Revelation 18:2 an angel with heavenly authority proclaimed the consequence of the Lamb’s victory: Fallen, fallen is Babylon the great!
and so she has become a dwelling place for demons and unclean spirits. In Revelation 18:4–20 the Lord issued a call to his people of all ages to distance themselves from the self-sufficient attitude of Babylon-like civilizations throughout history. There he also detailed the reaction of kings, merchants, and blue-collar workers—and the rejoicing of heaven—as incentive to follow the command to come out of her, my people.
The present passage relates what is to become of fallen Babylon (including why). This paragraph provides further incentive to God’s people to distance themselves from the mindset of Babylon and to be positive about the future.
21 Then a mighty angel took up a stone like a great millstone and threw it into the sea, saying, “So will Babylon the great city be thrown down with violence, and will be found no more;