That is the dead in Christ being resurrected and judged. The unsaved dead are not resurrected at the second coming.
2Ti 4:1 I charge thee therefore before God, and
the Lord Jesus Christ, who shall judge the quick and the dead at his appearing and his kingdom;
In the passage above Paul said the judgment of both the living and the dead comes at his appearing.
The judgment of the dead is found at the end of Revelation 20, and in Revelation 11:18.
(The same event.)
In 2 Thessalonians 1:7-10 Paul said the fire comes at Christ's return.
The fire comes at the end of Revelation 20.
This proves the Book of Revelation is not in chronological order. Instead, it is a series of overlapping visions.
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Multiple Second Coming Visions in Revelation:
(which prove the book is not in chronological order)
Christ returns at the end of Revelation chapter 6, with signs in the sun, moon, and stars, as are found in the Olivet Discourse.
Those at the end of the chapter are hiding from the wrath of the Lamb.
Why would they be hiding if Christ is not present?
The "kings", "captains", "might men", "free", and "bond" are also found in chapter 19 at the return of Christ.
He returns at the 7th trumpet, which is the last trumpet in the Bible, and the time of the judgment of the dead in Revelation 11:15-18.
The beginning of chapter 12 is a history lesson containing the fall of Satan, and the birth and death of Christ, who is the seed promised to crush the head of Satan in Genesis 3:15.
The Second Coming is found in the "harvest" of chapter 14, which is related to the parable of the wheat and tares in Matthew chapter 13.
He comes as a thief at Armageddon, and we find the greatest earthquake in history in chapter 16. This occurs when the 7th angel pours out his vial. How powerful is an earthquake which moves islands and destroys the mountains? What is happening to the planet?
He comes on a horse in chapter 19.
He comes with the fire, and the judgment of the dead at the end of chapter 20, which agrees with what Paul said in 2 Thessalonians 1:7-10, and 2 Timothy 4:1.
(The time of the judgment of the dead is also found in Revelation 11:18.)
There are no mortals left alive on the planet at the end of Matthew
25:31-46.
Why does an angel come down from heaven with a key to unlock the bottomless pit in Revelation 9:1-2, if the pit was not already locked?
Revelation
9:14 proves some of the angels have already been bound in some manner.
Because the two witnesses were bodily resurrected from the dead in Revelation 11, the "first resurrection" at the beginning of Revelation 20 is not the first bodily resurrection in the book.
The only way to properly interpret the book is through the principle of "Recapitulation".
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