The concept of the “rapture” is largely based on 1 Thessalonians 4:16-17: “For the Lord himself will descend from heaven with a shout, with the voice of the archangel and with the trumpet of God, and the dead in Christ will rise first.  Then we who are alive and remain will be caught up together with them in the clouds to meet the Lord in the air, and so we shall always be with the Lord.”  The Latin Vulgate Bible translation uses the word rapiemur for “caught up” meaning “we shall be snatched, we shall be grabbed, we shall be carried off.” This same Latin root is used to name a class of birds which swoop down and snatch up their prey – raptors.  From this, “rapture” was used in English to refer to this gathering of the last members of the followers of Jesus.

So, does the Bible say the gathering of believers is before or after the severe trouble which will mark the end of this age and the return of Christ?  The answer is both. Christ returns before the trouble to gather his bride, as described in the 1 Thessalonians 4:17 passage. The promise to the “overcomers” in the message to the church of Laodicea (the last period of church history before these end-time events) is, “He who overcomes, I will grant to him to sit down with me on my throne, as I also overcame and sat down with my Father on His throne” (Revelation 3:21). Matthew 19:28-29 says: “Jesus said to them, ‘Truly, I say to you, in the new world, when the Son of man shall sit on his glorious throne, you who have followed me will also sit on twelve thrones, judging the twelve tribes of Israel.  And every one who has left houses or brother or sisters or father or mother or children or lands, for my name’s sake, will receive a hundredfold, and inherit eternal life.’”

But then there is another group of believers whose position in heaven is not ON the throne, but rather BEFORE the throne. Revelation 7:9-17 says that this “great multitude” “came out of [or through] the great tribulation:” “After this I looked and behold, a great multitude which no man could number, from every nation, from all tribes, and peoples, and tongues, standing before the throne and before the Lamb, clothed in white robes. . . v. 13 Then one of the elders addressed me saying, ‘Who are these, clothed in white robes, and when have they come?’  I said to him, ‘Sir, you know.’ And he said to me, ‘These are they who have come out of the great tribulation; they have washed their robes and made them white in the blood of the Lamb.”  So, these believers were gathered during or after the tribulation.

Additional Resources: 
Christian Questions Podcast 
Episode #900: “So, When Does the Rapture Happen?” Biblically defining texts that seem to teach a rapture

3-Part Series: “Do I Suffer From Rapture Anxiety?
Questioning the rapture in the light of careful scriptural analysis

About the Great Multitude:
Episode #1250: What Will We Be Doing When We Get to Heaven? (Part III)
Learning the destiny of those not fully faithful to the heavenly call
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