These two verses contain many of the same words and phrases. In both instances, John is shown a vision revolving around a city, that is, Babylon and Jerusalem. The Babylon that John saw (Revelation 17:1) was depicted as a woman with a very self-seeking mindset resulting in behaviour (prostitution in conjunction with the world’s mighty) that sought to entice people to find their sense of well-being in the stuff of this world. The Jerusalem that John saw (here) was a glorious bride devoted to the Lamb, glorious beyond description. That John uses the same words in relation to these two cities sets the reader up to compare the two, and take note of their radical contrast. Specifically, the one is fallen and burned; the other is glorious and everlasting.
9 Then came one of the seven angels who had the seven bowls full of the seven last plagues and spoke to me, saying, “Come, I will show you the Bride, the wife of the Lamb.”