This is the first time that the name “Babylon” appears in Revelation (again in Revelation 16:19; Revelation 17:5; Revelation 18:2, Revelation 18:10, Revelation 18:21). The angel’s message that Babylon has fallen is an obvious allusion to the fulfillment of Isaiah 21:9. Babylon was the capital city of the Babylonian empire, notorious for its celebration of human ability (think Babel
in Genesis 11:1–32) and thus its rejection of any sense of dependence on God Almighty. Babylon represents the city and civilization and culture of human achievement, very much in contrast to the grace of God that was (intended to be) proclaimed and celebrated in Jerusalem (“Zion” in Revelation 14:1). If Jerusalem spoke of the glory and mercy of God in Jesus Christ, Babylon spoke of the brute force and cruelty of the dragon and his beasts.
8 Another angel, a second, followed, saying, “Fallen, fallen is Babylon the great, she who made all nations drink the wine of the passion of her sexual immorality.”