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 Thessalonians 2:3
suggested further reading: 1 John 2:18–25
So that the Thessalonians do not groundlessly promise themselves the joyful day of redemption in a short time, Paul offers them a melancholy prediction about the scattering of the church, declaring that believers must exercise warfare for a long period before gaining a triumph.
We have here a remarkable passage, and one that is worthy of observation in the highest degree. A grievous and dangerous temptation that might shake even the most confirmed believers and make them lose their footing would be to see the church, which had been raised up gradually and with difficulty and with much labor to some considerable standing, suddenly fall down, as if torn down by a tempest. Accordingly, Paul fortifies the minds, not merely of the Thessalonians but of all the pious, in advance, so that when the church does scatter, believers might not be alarmed as though it were a thing that was new and unpredicted.
Paul says that the day of Christ will not come until the world has fallen into apostasy and the reign of the antichrist has obtained a footing in the church. He uses the term falling away or apostasy to mean a treacherous departure from God, not just on the part of one or a few people, but a large multitude of persons. For when apostasy is mentioned without adding anything else, it cannot be restricted to a few.
Now, no one can be termed apostate unless he has previously made a profession of faith in Christ and the gospel. Paul therefore predicts a certain general revolt of the visible church. He says, “The church must be reduced to an unsightly and dreadful state of ruin, before its full restoration is effected.”
for meditation: God will establish his reign and kingdom; those plans cannot and will not be foiled. In light of this, we can know that whatever apostasies rock the church, she will not be destroyed. There is no reason for despair, and there is great reason for hope, because God—not the man of sin—is in control.