Every couple of years, it seems like there's a new end times doomsday scenario. Ten years ago, it was the Y2K computer bug, followed by the start of the 3rd Millennium in 2001. About that same time, the "Left Behind" series of books were gaining serious traction as the definitive novelization of the end of the world. Now it's the end of the ancient Mayan calendar in 2012, as depicted by the new blow-everything-up movie that's in theaters now. While the culture seems to be almost fearful of the end of the world, as Christians we should be anticipating and looking forward to the return of Christ at the end of time.
Much of what we understand about the End Times comes from the Scriptures, especially the Gospels and the Book of Revelation. Many groups, especially those who subscribe to the "Left Behind" rapture theory, read these passages in Scripture and talk about the coming of the End Times. As Catholics, we believe that we are already living in the End Times, and have been since Our Lord rose from the dead 2000 years ago.
The End Times are not some apocalyptic period that is yet to come, but a period of preparation by Christians for the return of Our Lord at the end of time. As Christians, we are living in this period of preparation now, as we should always be ready to greet Our Lord. He has promised that He will return again on "that day or hour [which] no one knows." (Mk 13:32)
While we don't know when Jesus will return, we do know what will happen on those Last Days. Jesus tells us that he will "'[come] in the clouds' with great power and glory." (Mk 13:26) The Prophet Daniel predicts that "those who sleep in the dust of the earth shall awake," meaning that our mortal bodies will be raised from the dead. Likewise, we are told "some shall live forever, others shall be an everlasting horror and disgrace," (Dn 12:2) foretelling the final judgment that we'll all have to face, with an eternity living forever in Heaven or everlasting horror and disgrace in Hell.
Deep down, I think this final judgment is the source of all the fear and uncertainty that drives the concern about the end of the world. Even for those who do not profess a belief in Christ, humanity seems to have a realization that we are fallen, sinful beings. The fear is that we might be wrong about what we believe and be condemned to the "everlasting horror and disgrace."
As Christians, we have a promise of hope. We are reminded in the Letter to the Hebrews that Jesus "offered one sacrifice for sins." Through Our Lord's sacrifice on the Cross, our humanity is to be perfected so that we can enter into eternity in Heaven. In fact, we can look forward with anticipation to when we will join Our Lord where He sits "at the right hand of God." (Heb 10:12)
St. Paul compares Our Lord's sacrifice with the sacrifices offered by the Jewish priests at the temple in Jerusalem, and with good reason. For any sacrifice to be beneficial for the ones offering the sacrifice, they must participate in the sacrifice itself. Just as the Jews had to participate in their sacrifices, we need to participate in the sacrifice of Our Lord. However, unlike the Jewish offerings that had to be repeated on a regular basis to ask forgiveness for sins, Our Lord's sacrifice was only offered once for forgiveness of all sins.
We participate in Our Lord's sacrifice every time we attend the Holy Sacrifice of the Mass and receive Our Lord in the form of bread and wine in Holy Communion. While Jesus' sacrifice only occurred once, we are in constant need of the graces which flow from the Sacrament to aid us in overcoming our sinful nature throughout our lives. This is why we don't say, "OK, I've received 1st Holy Communion. I don't have to attend Mass or receive Holy Communion again." We are fortified against sin every time we attend Mass and receive Holy Communion, but only if we desire to overcome our sinful nature. If we refuse to face our sins, we will block ourselves off from the full benefits of God's grace.
Because we participate in Our Lord's sacrifice on the Cross, we have no need to fear the end of the world and His return. Instead, may we look forward to that day with great joy and anticipation.