Apocalypse comes from a Greek word that means "uncovering," or a "revelation." In fact, the New Testament canon has as it's last book, "The Apocalypse of Jesus Christ," which is better known as "Revelation." That whole book is filled with visions that St. John of Patmos (traditionally, the "Beloved Disciple" of the Gospel of St. John) had while under incarceration.
Many images of the Apocalyptic tradition of Christianity are in the synoptic Gospels of Matthew, Mark and Luke. In Matthew, they are found in chapters 24 and 25. In Mark, the chapter is 13. In the Gospel of Luke, it is chapter 21. Matthew 24, Mark 13 and Luke 21 repeat each other, sometimes verbatim. Since, overall, these places could fill 2 or so chapters and not a book--they are called, "The Little Apocalypse." Matthew 25 has parables that are found no where else, save one, "The Parable of the Talents," found in verses 14-30. That parable is also found in Luke, but in somewhat different telling in an area outside of the Little Apocalypse.
There are basically 4 approaches to interpreting these visions. The first is Preterism. The second is the Historical interpretation. The Future approach is the third one listed. These three have to do different aspects of time. The final one is Philosophical, which is in essence, "timeless."
All of Mark 13 can be found in the other two Gospels. The only one of note is the last few verses which are not found in the Little Apocalypse section of Luke, but is found in chapter 17. Matthew's account is certainly closer to that of Mark, almost word-for-word, except in a few places. Matthew seems to add on to what Mark is saying. This is why Matthew's version of the Apocalypse is longer. Mark is the "Readers Digest" version, only in reverse, because it came first.
Luke's account has the most differences. Luke has a tendency to place elements outside his section that the others put in their own. Even so, Luke does have something in his chapter 21 that doesn't show up in Matthew's and Mark's account, no matter how similar they do appear to be in title. "Exhortation to Watch" sounds a lot like "Necessity of Watchfulness." These stories are essentially different, however. The "Necessity" as it is presented in both Matthew and Mark, is found elsewhere in Luke (chapter 12), so "Exhortation" is not the same.
Preterism describes things and events as they are occurring, or at best, a very short term "seeing" into the future, more like forecasting than predicting. Forecasting is different from predicting. Forecasting says the chances are likely to be this way as oppose to that way if current trends continue as they are. Predicting is more fatalistic. It says that things happen because they have to, regardless of the conditions involved. Preterists deny the possibility to "foresee" into the far future. This locks Preterism in the first century of our common era. This approach is popular among Roman Catholics, Episcopalian/Anglicans, Eastern Orthodox and free independent Catholics.
The Historical approach takes the view that one reads history, except looking forward into the future rather than looking back in the past. This allows the Historical school to be relevant for our current day and age as it was for everybody two thousand years ago as well as those who will come after us. Several of the Protestant reformers several centuries ago and a significant amount of mainline churches today take this approach.
The Future interpretation says that most of the prophecies of the Bible cannot be filled until the "end is near." People who take this approach say that the Apocalypse doesn't apply to anybody here today, unless, of course, some of us survive into a period of time commonly known as the "Tribulation," and especially the "Great Tribulation." The Apocalyptic lessons apply to those who live under the reign of a power crazed dictator and a religious leader that dominate the entire globe. Since this has neither happened in the past, nor is concurrent, the Apocalypse doesn't describe what humanity is going through up to this point. As of today, this idea is very popular among conservative evangelicals along with those who endorse any of the "millennial" viewpoints today, whether it be pre-trib, mid-trib or post-trib "rapture" of believers.
The only approach that doesn't involve time by itself is the Philosophical approach. Like Preterism, these folks deny the ability to foretell future events. But, we don't have too. What is eternal now was eternal in ages past and will continue to be so in ages ahead. Somethings simply go beyond change. Though it may appear that events and circumstances do morph and evolve as time goes on, things like liberty, justice, peace, joy, love and honesty will always remain defiantly constant. The Philosophical school of thought see these visions and images as a metaphor for spiritual battle that always takes place beyond our normal sight. "Good" will eventually win out because of it's eternal essence.
Since this week's Lectionary has the Gospel lesson of "The Parable of the Talents" (Matthew 25.14-30), it can be demonstrated that a combination of Philosophical and Preterism is adequate for our purpose of mining for spiritual gems. I'm not saying at this point that the other two are in someway invalid. Discovering the worthiness of all these interpretations will have to wait for another time. All I'm saying is that the first and last are at least valid enough for the insights we seek today.
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UPDATE: The Video Presentation: