Simply put... if you don't believe in the pre-trib you WILL be left behind
What is the Pretribulation Rapture?
The rapture is an event that will take place sometime in the near future. Jesus will come in the air, catch up the Church from the earth, and then return to heaven with the Church. The Apostle Paul gave a clear description of the rapture event in his letters to the Thessalonians and Corinthians.
"For the Lord himself shall descend from heaven with a shout, with the voice of the archangel, and with the trump of God: and the dead in Christ shall rise first: Then we which are alive and remain shall be caught up together with them in the clouds, to meet the Lord in the air: and so shall we ever be with the Lord. Wherefore comfort one another with these words." (1 Thess, 4:16-18).
"Behold, I shew you a mystery; We shall not all sleep, but we shall all be changed, In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed. For this corruptible must put on incorruption, and this mortal [must] put on immortality" (1 Cor. 15:51-53).
The timing of the rapture is not known. From the Word of God and from sound reasoning--something Jesus used quite frequently.
The word "rapture" comes from Paul's "caught up" remark in verse 17. The words "caught up" are translated from the Greek word harpazo, which means "to carry off," "snatch up," or "grasp hastily." The translation from harpazo to "rapture" involved two steps: first, harpazo became the Latin word raptus; second, raptus became the English word "rapture."
The Unknown Hour
When we search the Scriptures and read the passages describing the Lord Jesus' return, we find verses that tell us we won't know the day and hour of that event. Matthew 25:13 says Jesus will return at an unknown time, while Revelation 12:6 indicates that the Jews will have to wait on the Lord 1,260 days, starting when the Antichrist stands in the Temple of God and declares himself to be God (2 Thes 2:4). This event will take place at the mid-point of the seven-year tribulation (Dan 9:27). Note that some people only see a three-and-a-half-year tribulation. In a way, they are correct because the first half of the tribulation will be relatively peaceful compared to the second half. Nonetheless, peaceful or not, there still remains a seven-year period called the tribulation. When the Jews flee into the wilderness, they know that all they have to do is wait out those 1,260 days (Mat 24:16). There is no way to apply the phrase "neither the day nor the hour" to this situation. The only way for these two viewpoints to be true is to separate the two distinct events transpiring here: 1) the rapture of the Church, which comes before the tribulation; and 2) the return of Jesus to the earth, which takes place roughly seven years later.
The Marriage Supper of the Lamb
In Luke 12:36, the Word states that when Christ returns, He will be returning from a wedding. In Revelation 19:7-8, we read about the marriage itself. The marriage supper takes place before the marriage. According to Jewish custom, the marriage contract, which often includes a dowry, is drawn up first. The contract parallels the act of faith we use when we trust Jesus to be our Savior. The dowry is His life, which was used to purchase us. When it's time for the wedding, the groom goes to the bride's house unannounced. She comes out to meet him, and then he takes her to his father's house. This precisely correlates with the events according to the pre-trib scenario. Jesus, the Groom, comes down from heaven and calls up the Church, His Bride. After meeting in the air, He and His Bride return to His Father's house, heaven. The marriage supper itself will take place there, while down here on earth the final events of the tribulation will be playing out. After the marriage supper of Jewish tradition, the bride and groom are presented to the world as man and wife. This corresponds to the time when Jesus returns to earth accompanied by an army "clothed in fine linen, white and clean" (Rev 19:14).
What They Didn't Teach You in History Class
Many groups try to discredit the pre-trib rapture by saying most of the end-time events in the Bible have already taken place. A group of people called preterists claims that the Book of Revelation was mostly fulfilled by 70 AD. If the events described in the Book of Revelation took place in the past, I'm at a loss to explain some of the current situations I see around us: the rebirth of Israel, the reunification of Europe, the number of global wars that have occurred, and the development of nuclear weapons. During history class, I must have slept through the part where the teacher talked about the time when a third of the trees were burned up, 100-pound hailstones fell from the sky, and the sea turned into blood (Rev 8:7-8, 16:21). I think several people would have to question their opposition to the pre-trib rapture doctrine if they knew that the evidence provided to them was based on the understanding that most tribulation prophecies have already occurred.
The People of the Millennium
If Christ were to come back after the tribulation, rapture all the saints, and slay all the ungodly, who would be left to populate the earth during the millennium? Only the pre-trib viewpoint can account for this post-trib problem. The Church is raptured before the tribulation, a vast number of souls are saved during this seven-year time frame, and those who make it through the tribulation go into the millennium while the unsaved are cast into hell.
The Saint U-Turn
In the pre-trib scenario, after we rise to meet the Lord in the air, we will go to heaven and abide there seven years. At the end of that period, Christ will come down to earth, defeat the Antichrist, and cleanse the temple. In a post-trib rapture, we would rise in the air to meet the Lord, then do a 180-degree U-turn and come back down to earth. Revelation 1:7 states that Christ will appear out of the clouds and come down to earth. Zechariah 14:4 says that His feet will stand on the Mount of Olives. If He's already headed our way, why would we need to be caught up to meet Him?
"Come Up Hither"
Many pre-trib writers cite Revelation 4:1, which says, "come up hither," as a prophetic reference to the rapture of the Church, leaving Revelation chapters 1 through 3 as a description of the Church Age. After the shout to "come up hither," the Church is not mentioned in Scripture at all. The attention of Scripture switches from the Church to the Jews living in Israel.
Armies in Fine Linen
When Jesus returns (Rev. 19:18), an army follows Him. The army's members are riding on white horses, and they are clothed in fine linen that is white and clean. In Revelation 19:8, we are told that the fine linen is the righteousness of the saints. If the saints of God are returning with Christ to wage war on the Antichrist, then it is not possible to have a post-trib rapture without us running into ourselves as we are coming and going.
The Time of Jacob's Trouble
In several passages, the Bible refers to the tribulation as a time of trouble for the Jews. The phrase "Jacob's trouble" pertains to the descendants of Jacob. Jeremiah 30:7 says that this time of trouble will come just before the Lord returns to save His people. The final week of Daniel's 70th week is yet to take place. An angel told Daniel that, "70 weeks are determined unto thy people" (Dan 9:24). Scripture never mentions that the tribulation is meant to be a time of testing for Christians. However, some post-tribbers try to claim that they are the ones being tested during the tribulation. To make this so, they need to spiritualize the 144,000 Jewish believers in Revelation 7:2-8 who receive God's protective seal. Placing the Church dispensation into the same time frame as the seven-year Jewish dispensation, as the post-tribbers do, raises one good question: Can two dispensations transpire at the same time? In the past, God has only dealt with one at a time. Having both present during the tribulation would have to be an exception.
"He" That is Taken Out of the Way
Before the Antichrist can be revealed, Paul said a certain "He" must be taken out of the way. According to 2 Thessalonians 2:7, the "He" that must be removed is widely thought to be the Holy Spirit. It has been promised that the Holy Spirit would never leave the Church, and without the working of the Holy Spirit remaining on earth, no one could be saved during the tribulation. The removal of the Church, which is indwelt by the Holy Ghost, would seem the best explanation for this dilemma. The working of the Holy Spirit could go on during the tribulation, but His influence would be diminished because of the missing Church.
War or Rapture
(Rev 19:19-21) When Jesus returns at the end of the tribulation, He will be coming for battle. For those who believe in a post-trib rapture, it would be strange to meet your Lord and Savior just as He's rushing into battle. The idea that war and rapture could occur together is difficult to imagine, especially since they transpire at the same moment.
The Five Foolish Virgins
The wedding story that Jesus gave in Matthew 25:2-13, I believe, is a parable of the rapture of the Church. It explains how some will not be ready. Jesus clearly states that a group of people will miss out on an event, and will cry out to God to let them into the place where He resides, heaven. Although some try to put this parable in a post-trib context, it doesn't fit very well. The ones left behind in a post-trib rapture will not need to seek the Lord because they'll immediately be confronted by Him and His army of angels.
God Hath Not Appointed Us to Wrath
In 1 Thessalonians 5:9, Paul assures us that God has not appointed His people to wrath. This wrath is plainly God's anger that will be poured out during the tribulation. Pre-trib believers interpret this as meaning that Christians will be removed from the earth. Post-trib believers tell a different story. They describe this as meaning that God will protect Christians during the tribulation and pour this wrath out on the unbelievers only. This idea runs against the statement made in Revelation 13:7, in which the Antichrist is given power to make war with the saints and to overcome them. A post-trib view would make God's promise of protection from wrath into a lie. In years past, it was possible to think of being protected from the guns and swords of that day. Today, when any major war would involve nuclear and chemical weapons, it's impossible to expect that same kind of protection. When Nagasaki, Japan was bombed during World War II, the bomb exploded over a Catholic church. Everyone who was in the center of the explosion died--both Christians and non-Christians. The only way to validly interpret God's promise of protection from wrath is by viewing 1 Thessalonians 5:9 as the bodily removal of the Church from this world.
The Salt of the Earth
Jesus said, "Ye are the salt of the earth" (Matthew 5:13). When the believers are supenly removed, the earth will be plunged into spiritual darkness. When this happens, the Antichrist will then be free to control the world.