As a continuation of my last post, where I made some points about Genesis-prophecies of a pre-tribulation rapture of sorts (in Noah and Lot), I thought I'd add a little about points for the "other side".
First, let me say that I don't think the stories of Noah and Lot prove a pre-tribulation rapture, nor was I meaning to say that they do. Simply, there are some seeming prophetic types for a pre-tribulation rapture. Questions to take from that post are: is it a saving from all end-time tribulation, or just the final big bang? is it a complete evacuation of earth by all the faithful, or simply vacating the "area" of tribulation (if some see the final bang as happening in Jerusalem or Rome, or wherever)? Indeed, in both cases the faithful were taken away from the area of disaster; in Noah's case, the area of disaster was the entire planet, and in Lot's an area of cities. Further research into the area of end-time disaster is clearly required.
Anyway, many end-time theorists utilize the words of Jesus about the end being a harvest, particularly in the Parable of the Sower in Matthew 13 (v 39: "the harvest is the end of the age"). The premise is basically that there are weeds sown in among the wheat, and that the Master does not want to uproot the weeds presently for fear of losing some of the good wheat. Instead, he leaves it to the end, and begins then by pulling up the weeds and throwing them into the fire. Then, the remaining wheat is harvested.
This speaks to me about a great persecution more than an escape from persecution actually. The acts of pulling up weeds and using a sickle to remove the wheat from its roots are both violent and involve pain for the plants, if they could feel pain. Is this in reference to some sort of end time delusion or mass-test? Those who will not die for the truth are kept alive on earth to face the final apocalypse, while those who die for Christ (are cut down, as the wheat is) are "harvested" into the arms of their Savior in heaven, and return later with him?
The end time is also prophetically symbolized by the "threshing floor", which is mentioned frequently in conjunction with a winepress in the Old Testament. Literally, sheaves were laid on the circular threshing floor, and were trodden by oxen hitched to a central pivotal point. To me, this process of separating the wheat from the chaff (not speaking of separating weeds from grain) speaks of a negative or persecutory experience for the "grain" or the believer. But the process is not ended there.
The second part of the process of the threshing floor takes into account the wind. The farmer uses a winnowing fork and begins to throw up the trodden mess into the air to be caught by the wind. "The wind would blow the lighter chaff to one side, while the heavier grain would fall into a pile, which could then be gathered." (more info). Now, this seems to be an implication of another "going up", and is very symbolic of some sort of rapture. The question remains whether this is the rapture experienced by a Christian upon death (the normal going to heaven; just so happens to be that all of the Christians are put to death around the same time), or a mass evacuation preceded by a test of some sort to see who is faithful. I would lean towards a large-scale persecution, a mass abandonment of the faith (as predicted in Matthew 24:10-12), and a removal of the faithful by martyrdom - the gathering of the Lord.
"Take your sickle and reap, because the time to reap has come, for the harvest of the earth is ripe." Revelation 14:15
The above verse from Revelation is from a section called "The Harvest of the Earth", and is alongside another "type" of harvest, which is that of grapes in the winepress. Verses 17 to 20 speak of something violent coming against the faithful, for the grapes are being harvested (ie. the grapes represent the sons of the Kingdom), and they are "trampled" in the winepress, and "blood" flows out of the winepress as high as the horses' bridles (not grape juice, but blood). I don't think this one needs much more of an explanation; perhaps it brings more light to the words of Christ in Luke 18:8: "However, when the Son of Man comes, will he find faith on the earth?"
Pre-trib rapture theorists are often challenged by the assertion of the "other side" that there is an absense of logic in the fact that end-time Christians are spared persecution and martyrdom while Christians have been dying for their faith in Christ since he left earth. What many on both sides forget is that in this last century alone, more Christians were killed for their faith than in every other century prior COMBINED. Seems the harvest has begun!
My final point about a rapture of spirits out of martyred bodies at the end of days is the events following Revelation's Harvest - the Seven Bowls of God's Wrath (ch. 16). The third bowl is poured out on the water supplies of the earth so they become blood (familiar with the plague of blood by Moses). This angel proclaims the reason for doing so: "they have shed the blood of your saints and prophets, and you have given them blood to drink as they deserve" (16:6). This effects the drinking water for the whole earth, not just one country or city, which implicates a. the kingdom of the beast (the first whole-world kingdom), and b. that a proportional judgment has come upon the guilty generation (ie. a fair "repayment" for those who caused the martyrdom), and c. that all who drank from the water before it became blood are guilty of the genocide. A great delusion, indeed.
"God sends them a powerful delusion" (2 Thess 2:11)
I've often wondered about the number of people who would be included in a theoritical disappearing of Christians. I thought that many would be "left behind" who thought they shouldn't be, and this would be the source of great mourning, as I am a believer that the true church is much much smaller than the seen church. The only thing that could really test the faith of someone who fits into the "many are called, few are chosen" category would be a threat against their life. Perhaps a gun to their head. Perhaps a cattle car heading to an extermination camp. We saw how few Christians went to the Nazi camps for not participating in the genocide. A mass delusion then? Most certainly. A mass delusion at the end? More certainly.
"You will be handed over to be persecuted and put to death, and you will be hated by all nations because of me. At that time many will turn away from the faith and will betray and hate each other... he who stands firm to the end will be saved." Matthew 24 portions