Yet another voice from heaven calls God’s people out of Babylon. Both Isaiah and Jeremiah called on Israel to flee Babylon; John is using language from both prophets to call for another exodus out of Babylon.
In a clear allusion to the original Exodus, Isaiah 52:11 tells the people to depart from Babylon. They are not to go out in haste because God himself will lead them and also be their “rear guard.” Since Revelation has frequently alluded to the ten plagues to describe the ongoing judgment of the kingdom of the beast, it should be no surprise John picks up on the language of the Exodus to call his people to flee Babylon. Revelation 18:4 and Isaiah 52:12 both use the aorist imperative ἐξέλθατε, “come out.”
Jeremiah 50:8-10 calls on Israel to flee Babylon because God is stirring up the nations to plunder her. Rather than the Exodus, Jeremiah is looking forward to the fall of Babylon when nations from the north (Persia and the Medes) plunder the Babylonian empire. Jeremiah 51:6-10 is clearly in the background of Revelation 18:4-8. Jeremiah describes Babylon as a fallen and broken woman. Like Revelation 18:5, her judgment has “reached up to heaven” (51:9).
If Babylon refers to Rome in Revelation 17-18, some scholars suggest Revelation 18 is a call for Christians to leave the literal city of Rome (perhaps in anticipation of persecution). However, just as the call to “come out of Babylon” in Isaiah and Jeremiah referred to leaving the Babylonian empire in general, John’s intention is for God’s people to leave the Roman Empire. This cannot mean leave Rome and go to another place, since there is no other place to go! As David Aune says, this is a “the summons to flee from the city is used symbolically, with the city referring to the demonic social and political power structure that constituted the Roman empire” (Revelation, 3:991).
The reason they are to “come out” is so that they do not share in her sins, her since are “piled up to heaven” and God remembers her crimes. After the exile, Ezra confessed guilt “as high as the heavens” (Ezra 9:6). If they share in her sins, they will also share in the plagues which punish those sins.
Babylon’s judgment will repay her double for what she has done, a clear allusion to Jeremiah 50:29 (cf. 51:24). The Lord will give her a double portion of punishment to drink, as much torture and grief as she gave herself luxury
In Revelation 18:4-8 God’s people are called to separate from the social structure of the Roman world. This is a radical calling that is consistent with the rest of Revelation. In the Seven Letters believers are called to live different from prevailing culture, later they resist the power of the beast and refuse to take the mark of the beast even though this results in their death.
This is perhaps the most challenging portion of Revelation for Christians living in various cultures and times in history. How should Christians “come out of Babylon” today? How do we refuse the “demonic social and political power structure” and not take part in the sins of contemporary culture? As 2 Corinthians 6:17 says, God’s people are called to be separate from the world, “touching no unclean thing.” This is not just talking about clear, ugly sins, but also participation in a political and social structure that is objectively evil.
In the context of Revelation, there are people claim to be Christians who do not separate from the world and do in fact “touch unclean things,” Jezebel (2:20) and Balaam (2:14), the Nicolaitans (2:6, 15) and those who worship the beast and take his number. These are Christians who think they are serving God while they participate in the imperial cult and all that comes along with that. Although the details are different, it is clear many Christians today have little trouble supporting and participating in modern demonic social and political power structures.