I'm a Pre-Tribber myself. A pretribulation Rapture is essential for a number of reasons: first of all, to remove true Christians from earth. If they were present when Antichrist was revealed, they would oppose and expose him. This opposition must be removed in order to give Satan and man, under Antichrist's leadership, full freedom to prove that this earth can be turned back into a garden paradise without God. The Holy Spirit, who is present everywhere, will still convict and draw many to Christ during the Great Tribulation. The restraining influence, however, which He has wielded in this world through the millions of true Christians, will have suddenly been removed, leaving a moral and spiritual vacuum in homes, neighborhoods, businesses, and schools such as we cannot even imagine.
A pretrib Rapture is also necessary because the Antichrist will be given authority by God "to make war with the saints, and to overcome them" (Rev. 13:7). Such a fate could not befall the church, for Christ said that the "gates of hell shall not prevail against it" (The Church) (Matt. 16:1

. Moreover, true Christians have authority and power to "resist the devel" and "he will flee" (James 4:7), for "greater is he that is in you (us), than he that is in the world" (1 John 4:4). So the fact that Antichrist is given power by God "to make war with the saints and to overcome (i.e., kill) them" is proof that the true church is no longer present. The "saints" mentioned are those who have not heard and rejected the gospel prior to the Rapture and who believe in Christ during the Great Tribulation. They will pay for their faith with their lives. Those who take the mark of the best suffer the wrath of the Lamb, while those who don't are slain by Antichrist. Thus a post-trib rapture would be a classic nonevent, for there would be very few if any surviving believers to be raptured at that time. And surely those Christians who were left alive, seeing the judgment of God poured out upon mankind and earth's armies gathered for the battle of Armageddon in an attempt to destroy Israel, would know beyond the sahdow of a doubt that the Second Coming was about to occur--and would be watching for their Lord to appear. Yet Christ declared that He would return at a time of such ease that even the "five wise virgins" would "slumber and sleep." He warned, "for in such an hour as ye think not the Son of man cometh" (Matt 24:44). Hardly likely in the midst of the greatest tribulation and destruction the world has ever seen or ever will see!!
Buck