Presenting a second post on conspiracy theories:
Alexander Hislop's book The Two Babylons is sadly still regarded by many as a work of outstanding scholarship and a great help in the controversy with Rome. Ralph Woodrow, among others, has shown that it is neither. The great problem with Hislop's approach is that it is arbitrary and can be used to prove anything (and therefore it actually proves nothing).
Put simply, the Hislop Hypothesis is that the worship of the Roman Catholic Church today is practically identical to that of the ancient Babylonian Mystery Religion, and that the Roman Catholic Church is nothing more than paganism Christianized.
The greatest problem with Hislop's thesis is that it does not fit the facts, and therefore the facts have to be massaged to fit it. All must be placed on Hislop's Procrustean bed and forced to fit! The second problem is that the method, if applied consistently, ends with the claims of Dan Brown that there is nothing original in Christianity! Why? Because similarity (even a similarity that, on closer examination, proves to be nothing of the kind) is enough for Hislop to establish a link. The Babylonians had a celibate priesthood, so does Rome! No, the Babylonians had priests who were Eunuchs. There is a slight difference here! Where this sort of thing leads those who do not hold on to Hislop's relatively orthodox Presbyterianism is to make like Dan Barker in the now-notorious debate with James White, claiming that Mark must have borrowed from Homer because in Homer's Oddysey they got into a boat and sat down, and in Mark's Gospel they got into a boat and sat down. Really? You know what I did last time I got into a boat? I sat down.
Let me repeat, that two people do something similar does not prove a connection. The Medieval dualist sect called the Bogomils believed that Jesus and Satan were brothers, sone of the most high God, but Satan disobeyed and became evil, while Jesus was obedient. The Mormons believe essentially the same thing. Does this prove that Mormonism is nothing other than a continuation of Bogomilism? Of course not! As Yuri Stoyanov has shown in his book The Other God, the dualist heresy has resurfaced time and again through history with no apparent connections to previous dualist groups. Thus similarity, even of belief, cannot prove a connection. How much less can a mere similarity of form? And that is even if one exists!
And another thing, there was no "Babylonian Mystery Religion". The Mystery religions (plural!) originated in many areas, Greece, Egypt, Phrygia, Syria and Persia (see Romanld H. Nash: The Gospel and the Greeks [P. & R., 2003]. Nash is undoing some of the damage caused by Hislop's recklessness). None of the chief mystery religions originated in Babylon, and the Persian mystery was that of Mithras, not a worship of Nimrod. Hislop conflates dozens of gods from a score of nations to produce his own mythic Nimrod. In his zeal against Rome he forgot the first rule of controversy - be fair. If you can pick and choose bits from all over antiquity to make your "Babylonian Mystery Religion," you can make it look like anything you want! Which of course fits very well if you want to make Rome look pagan.
Hislop was not a historian or a student of Babylonian culture, he was a parish minister with a bee in his bonnet about the Church of Rome who was not too particular what arguments he used against it. The main thing was that the arguments were against Rome!
To summarize. There are many faults with the Church of Rome, and these have beeen laid out in such books as Dr. James R. White's The Roman Catholic Controversy, Eric Svedsen's Evangelical Answers and McCarthy's The Gospel According to Rome. The objections are doctrinal, rooted in Rome's exaltation of the pope, her doctrine of justification and merits, and her undue exaltation of the Virgin Mary, to name just three points. None of these are derived from Babylon. It may fairly be argued that Romanism is "Christianity paganized", to paraphrase Thomas E. Peck, it cannot be argued that it is Paganism Christianized.
Christians ought not to read Hislop's book. As he was Free Church minister of Arbroath, I can only conclude that the book is the result of too many kippers! Joking aside, The Two Babylons will not prepare any Christian to answer the claims of Rome, and Rome has no doubt answers to it - such as the obvious one that it is chock-full of errors. Thus, if a person's opposition to Rome is built on a myth, they can easily be shaken from it. But, if it is based on facts, then it is going to be much more stable.