This Bible chapter is describing a great mystery about the Mother of all prostitutes. She is obviously guilty of religious fornication and of abominations. In other words she is guilty of sleeping around religiously-speaking, employing all kinds of different pagan and unsound doctrines, which to me means that she's playing the field with different religions that have nothing to do with the truth.
The scary part of all of this is that she is commonly identified euphemistically as 'Rome', meaning the Roman Catholic church, which fit all the clues given in the description in this chapter.
The Vatican City sits on seven hills, is a sovereign country as well as being a great city and rules religiously over any Roman Catholic monarchs and appointed Catholic heads of world governments.
The King of this country is a leader who is hungry for power; calling for all other religious groups to come under his dominion and claiming to be the only church that has the power to grant salvation. The Catholic Church has stated and believes that anyone outside of Catholicism is lost and without salvation. This is outright religious blackmail and there is absolutely no truth in their claim.
In fact, the Biblical indictment of the Roman Catholic church also jeopardises the claims of Christianity as a whole, because there is little or no real difference in the doctrines of the mainstream Christian faiths, such as the Greek/Eastern Orthodox, Roman Catholic (except for their Mariology) and Protestant groups.
To understand Revelation 17, it is necessary to look at in the context of other parts of the Bible.
The seven hills on which this city sits are also seven heads or kings; five have fallen, one is and one is to come for a little while. (verse 10) The revelation of this prophesy came out in the 1990's, when Pope John Paul II was reigning. He was the sixth sovereign Pope of the smallest country in the world - only the five Popes before him had been crowned as kings of the Vatican, as well as being its Papal heads. Note the seven are described as 'heads' and as 'kings' which are dual positions these Popes held. There is a specific reason for them being crowned as kings, which will become obvious later.
In verses 8 and 11, it describes the 8thHead or king as being of the seven Papal kings and as 'the Beast that was, is not' and he shall come out of the bottomless pit, and go to perdition. The interesting part is that the whole world will marvel when they see this Beast, especially because he was [alive], is not [alive now], yet will be [present in person].
Here you see how much Satan wants to be God, that he mimics God - he is even going to 'resurrect' his own son; who is the son of perdition and the man of sin, as described elsewhere in the Bible. The only person described in the Bible as the 'a devil' (John 6:70) and as the 'son of perdition' (John 17:12) is Judas Iscariot, the traitor disciple.
Obviously, he can't come as himself because no one will pay him the slightest bit of attention. However, the devil is a conniver, and he has set up his son to appear as 'Jesus Christ at his second coming'. This is why and how the whole world will marvel at his appearance. To top it off, if he is coming as the 'eighth' head / king of the Papacy, it is obvious that he will be the next Pope.
John Paul II was the sixth head/king, the current and seventh pope is Pope Benedict XVI, who is to 'continue for a short time' (Verse 10). This all ties in with so much other information that is available from the Bible but is far too much to go into here.
Can you imagine how he will appear on the world's centre stage? I suspect that he is going to emerge from the airtight security of the next Papal conclave, which it would have been impossible for him to enter, except by supernatural means. His exit will be accompanied, again in mimic of the appearing of the true Son of God, by the lightning flashing from east to west (Matthew 24:27) of the flashbulbs of the world's photographers.
He appearing will be so convincing, it would fool even the elect, if that were possible. (Matthew 24:24 & Mark 13:22)
Can you imagine the effect of this appearance? It is going to unite all of Christendom under the umbrella of the Roman Catholic church and even put Christian nations, such as America, Britain, Australia, etc. under the rule of the returned Jesus (Verse 18). These Christian nations, I believe, will number ten (Verse 12) in all and when they eventually realise how they have been fooled, that is when they will turn against the Vatican and obliterate it completely in the short space of one hour (Verse 16).
Other nations and other religions will be hard put to ignore this final proof of the truth and exclusivity of the Christian faith with the appearing of their Lord and Saviour. This is the reason that Jesus will not only be a religious world leader or 'head', but as the King of a sovereign country, he will also be on a par with other kings and world leaders, irrespective of their nationality or religion, and will receive their homage.
Conversely, those whose names are 'written in the Book of Life from the foundation of the world' (Verse 8) will not marvel when they see the Beast, simply because they know beforehand of his coming, also exactly who he is, and what to expect from him.
Revelation 13:8 says that the whole world whose names are not written in the Book of Life will worship him. Here this chapter is speaking of the Beast from the Sea who is the same person doing the same things, which increases our composite picture of who this Beast is and what he will do.
He will make war with the Saints and overcome them (Revelation 13:7 & Daniel 7:21; 12:7) in a tribulation / holocaust so great that no one has ever seen it before or will ever see it again (Matthew 24:21, John 16:33, Acts 14:22, Romans 5:3, Revelation 2:10), which is to 'refine them [the saints] and make them white'. (Daniel 11:35 & 12:10).
Basically, anyone not bowing their knee to this returned Jesus will be left standing up, and standing out like a sore thumb, so that they will be arrested, persecuted, brought before councils (Matthew 10:16-42, Matthew 24, Mark 8:34-38, Mark 13, Luke 9:23-26, Luke Chapters 12 & 13, Luke 21:7 - 26, John 15:18 - 16:4.) and beheaded in execution (Revelation 20:4) - having taken up their crosses to follow their Master;
And this is how the 'Whore of Babylon' becomes drunk with the blood of the martyred Saints (Revelation 17:6).
Revelation 7:9-17 describes those who have endured the Tribulation and finished the race, collected their crowns, and become priests of God and of His Son.
'Blessed and holy is he who has part in the first resurrection. Over such the second death has no power, but they shall be priests of God and of the Messiah and shall reign within him a thousand years.' (Revelation 20:6)