With just a little research at your local library you can easily trace the origin of the Rapture theory to Glasgow, Scotland, to the year 1830 when Margaret MacDonald, a mentally ill woman, had a vision whereby the Lord descends in the clouds and calls His saints to rise up and meet Him in the air.
The Pre-trib theory is the most prevalent and states that Christ returns before the tribulation of Antichrist and “takes away” His church.
I suppose what is most amazing about the Rapture theory is that the Bible is not unclear at all about when Jesus Christ returns. He returns at the seventh trump, the last trump, after Antichrist has been standing in Jerusalem claiming he is God.
2 Thes. 2:1
Now we beseech you, brethren, by the coming of our Lord Jesus Christ, and by our gathering together unto Him,
The subject is “the coming of our Lord Jesus Christ, and our gathering unto Him”.
2 Thess: That ye be not soon shaken in mind, or be troubled, neither by spirit, nor by word, nor by letter as from us, as that the day of Christ is at hand.
Paul is saying “don’t be confused about when Christ returns, whether someone tells you to believe their ‘version’ or some Bible thumper twists chapter 4 verses 16-17 of my first letter to you, 1st Thessalonians.”
2 Thess: Let no man deceive you by any means: for that day shall not come, except there come a falling away first, and that man of sin be revealed, the son of perdition;
2 Thess: Who opposeth and exalteth himself above all that is called God, or that is worshipped; so that he as God sitteth in the temple of God, shewing himself that he is God.