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In this passage, Paul speaks of the consoloation all believers have in the resurrection of the dead at the return of Christ. He very clearly says that the resurrection will occur at the return of Christ and the dead in Christ will rise first before all the faithful, both resurrected and those who are alive at Christ's return, are gathered to be with Christ. The fact that the hope he holds out to those who have lost faithful loved ones is resurrection is important because at that time, just as today, there is a belief that one has an immortal soul which goes to heaven to be with the Lord at death. This is false teaching with a pagan origin.
Read what Paul says in 1 Corinthians 15:12-18 Now if Christ is preached that He has been raised from the dead, how do some among you say that there is no resurrection of the dead? But if there is no resurrection of the dead, then Christ is not risen. And if Christ is not risen, then our preaching is empty and your faith is also empty. Yes, and we are found false witnesses of God, because we have testified of God that He raised up Christ, whom He did not raise up––if in fact the dead do not rise. For if the dead do not rise, then Christ is not risen. And if Christ is not risen, your faith is futile; you are still in your sins! Then also those who have fallen asleep in Christ have perished. Notice that he says that if there is no resurrection then those who have died in Christ have perished. In the Greek that word perished is apollumi and means to be utterly destroyed.
Verse 17 is the verse commonly used to justify the notion of the "Rapture." The "Rapture theory" as it is usually portrayed is false. The actual word "rapture" is not mentioned in the Bible. The concept is taken from a mis-reading of verse 17. The Greek word for "caught up" in 1 Thess. 4:17 should be translated "caught away" as the top-drawer lexicons inform us (Nestle, Vines, Kittel-Friedrich) and is so rendered in Acts 8:39.
The logic of translating the word as "caught up" is poor. If we are caught "up" to meet the Lord "in the air" there are limitations in terms of altitude which makes the idea not sound. Are we to believe that Jesus and the saints will be in that narrow band of atmosphere - at most 20,000 feet or so (and that's being generous) when he comes?
However, having the saints caught away to be with the Lord on the earth (i.e. not "over the earth") when he comes, makes sense. If you are being taught that the saints are being caught away to a place of judgement before being revealed to the rest of the world, that's a pretty accurate picture. The point is that we are not caught away to be floating in the sky forever or caught away to heaven. We are told that when he returns, the Lord's feet will stand on the Mount of Olives. To be with him, we will have to be taken there "caught away" as Philip was in Acts 8:39. Jesus is coming all the way back to the earth, not just part of the way.
"In the air" is significant because for those raised from the dead. They will be taken from the depths of the earth to once again be "in the air." The air just means the atmosphere; a place where respiration is possible. The term "clouds" is used in Hebrews 12:1 to describe the great number of the faithful. Thessalonians is not talking about the saints going up to meet the Lord in low orbit as he returns (but not quite all the way) to the earth. It is a picture of the faithful being taken away as that "great cloud of witnesses" to be with their Lord when he returns to the earth - all the way to the earth - and establishes his Father's glorious kingdom.
Here is some information on our website which you might find useful: Christ Is Coming (Click on the title)
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