Although I have a Master's Degree in Theology and read my Bible daily, I am by no means a Biblical scholar. One of the books of the Bible that has always mystified me is the Book of Revelation. I have always viewed it as a terrifying vision of the future. I recently read "Revelation: A Divine Message of Hope" by Father Bruce Vawter. This small book (60 pps) provided a wonderful introduction and background to the Book of Revelation. Father Vawter explains it's roots in the Old Testament and how the writer John used terms his Jewish audience would be familiar with. He also explains the symbolism of the numbers used. It was extremely informative and enlightening and made it all seem much less frightening. Father Vawter also describes the apocalyptic vision as one taking place at all times. It is both now and not yet.
I would highly recommend this book for anyone who, like me, has failed to understand the Book of Revelation. It is available as a free download at : Catholic Information Service. It can also be purchased in book format for a low price. It is one of the "Veritas" series. While you are there, you might find other booklets that would interest you as well.