Past or future?
The book of Revelation can be hard to understand and there are a lot of interpretations of it. One area of disagreement is whether some parts of it have been fulfilled already or whether all of it still lies in the future. The answer to this question can be found within the book itself.
Near the start of the book the Lamb is given a scroll sealed with seven seals. He begins opening the seals and something happens when each seal is opened. Here is what happens when he opens the fourth seal.
And I looked, and behold, a pale horse! And its rider’s name was Death, and Hades followed him. And they were given authority over a fourth of the earth, to kill with sword and with famine and with pestilence and by wild beasts of the earth. (Revelation 6:8)
After the fourth seal was opened one fourth of the world’s population was killed. Has anything like that happened yet? There have been times when most of the population of a small area has died but we have never seen one fourth of the earth’s population destroyed. In the last century there have been two world wars in which millions of people died but the death toll of those wars was much less that a fourth of the earth.
If the fulfillment of this prophecy is still future the rest of the book is too.
Revelation starts with a statement that seems to contradict this.
The revelation of Jesus Christ, which God gave him to show to his servants the things that must soon take place. He made it known by sending his angel to his servant John. (Revelation 1:1)
If the things written in this book must soon take place, then surely they must have already begun. God’s idea of soon doesn’t always agree with ours. Second Peter 3:8 says,
But do not overlook this one fact, beloved, that with the Lord one day is as a thousand years, and a thousand years as one day.
From God’s point of view less that two days have elapsed since John wrote Revelation, so to him it is still soon.
If you want to learn more about Bible prophecy I recommend two sites called raptureforums.com and raptureready.com. Here are the links to these sites.