"17 Then one of the seven angels who had the seven bowls came and said to me, “Come, I will show you the judgment of the great whore who is seated on many waters, 2 with whom the kings of the earth have committed fornication, and with the wine of whose fornication the inhabitants of the earth have become drunk.” 3 So he carried me away in the spirit into a wilderness, and I saw a woman sitting on a scarlet beast that was full of blasphemous names, and it had seven heads and ten horns. 4 The woman was clothed in purple and scarlet, and adorned with gold and jewels and pearls, holding in her hand a golden cup full of abominations and the impurities of her fornication; 5 and on her forehead was written a name, a mystery: “Babylon the great, mother of whores and of earth’s abominations.” 6 And I saw that the woman was drunk with the blood of the saints and the blood of the witnesses to Jesus.
When I saw her, I was greatly amazed. 7 But the angel said to me, “Why are you so amazed? I will tell you the mystery of the woman, and of the beast with seven heads and ten horns that carries her. 8 The beast that you saw was, and is not, and is about to ascend from the bottomless pit and go to destruction. And the inhabitants of the earth, whose names have not been written in the book of life from the foundation of the world, will be amazed when they see the beast, because it was and is not and is to come.
9 “This calls for a mind that has wisdom: the seven heads are seven mountains on which the woman is seated..."
I stopped in the middle of the last verse because the second part goes into who the kings are and the writers of commentary have specific theories about who this refers to and it also varies by which time period they are writing in.
I have to admit as a female I blanche at the use of the word 'whore' and at the characterization of this city as a female but it's important to realize that though she is characterized as female it seems that what the text is talking about has to do with the idolatries of greed and materialism and also persecution of Jews and Christians (in addition to the obvious symbolism of the Roman Empire and the seven hills on which it was founded).
The Bible seems to be using promiscuity once again as a metaphor for the idolatry that both individuals and nations have practiced historically when it comes to putting false Gods above our worship for God and Christ. That can refer to pagan idolatry or it can refer to greed, lust, material comfort or anything else we put in front of living our lives for God.
In the first part of the sentence in verse nine the writer refers to seven mountains the city is founded on, which possibly refer to the seven hills upon which Rome was said to have founded. The writer at gotquestions.org goes into more detail about this and points out that this passage also refers to kings and doesn't therefore exclusively point to Rome but spiritual adultery in general; that is, the whore of Babylon sitting on the dragon refers to the idolatry of God's children with false Gods and worldly values, which signify adultery in His eyes.
When we think about how Christ uses the metaphor 'bride' to signify the body of Christ it becomes clear that we are in a sense spiritually married to Christ when we accept Salvation from Him. In verse eight, John of Patmos again drives home the fact that the beast from which all of these idols draw their power is going to 'go into destruction', as will everyone that has not had their name written in the book of life. I hope that everyone will make the choice today to accept Christ as Lord and Savior to avoid this fate.
If you want to accept Salvation from Christ here are some resources:
A Prayer for Salvation from Christ:
Lord
Jesus, I confess my sins and ask for your forgiveness. Please come into
my heart as my Lord and Savior. Take complete control of my life and
help me to walk in Your footsteps daily by the power of the Holy Spirit.
Thank you Lord for saving me and for answering my prayer.
A more detailed step by step process:
https://www.wikihow.com/Accept-Jesus-Into-Your-Life