The day of the Lord (2:1-12)
Some of the Thessalonians thought that the final day of the Lord had already come. Paul states firmly that they did not get such an idea from any prophecy, preaching or letter of his (2:1-2). That day will not come until there is open and widespread rebellion against God, led by one known as the man of lawlessness (RSV; NIV) or the wicked one (GNB). This person will recognize no authority, Christian or otherwise, apart from his own, and will put himself in the place of God as the sole controller of human society (3-4).
The Thessalonians knew what Paul was talking about, because he had given teaching on these things while among them (5). They also knew what we do not, namely, what or who it is that prevents these things from happening now. One suggestion is that this restraining power is the system of law and government that to some extent can control evil in human society (cf. Rom 13:3-4). Evil is always at work in the world, but when the restraining power is removed, evil will reign unhindered till it reaches its fulness in the man of lawlessness. Then Christ will return and with terrible ease destroy him (6-8).
During his rise to power the man of lawlessness will be empowered by Satan to perform miracles. In this way he will deceive people who, having deliberately rejected God and chosen evil, give him their support and so fall under God’s judgment. God will use the unrestrained work of Satan as a means of punishing a rebellious world (9-12).
2:13-3:18 PRESENT NEEDS IN THE CHURCH
Stability amid persecution (2:13-3:5)
From considering the terrible judgment that awaits the wicked, Paul turns to look at the bright future that awaits the Thessalonian believers. God will destroy the man of lawlessness and his followers, but the same God loves the Thessalonian believers. Their salvation is certain because God chose them as his from eternity, called them to himself through the gospel, and will in due course give them a share in Christ’s glory (13-14).
In view of the security that is theirs through the gospel, the Thessalonians need not be frightened by persecution or worried about future events. If they hold firmly to the apostolic teaching given to them, they will find that God strengthens them with courage and hope (15-17).
Paul asks for prayer that his proclamation of the gospel in Corinth will bring the same fruitful results as it did in Thessalonica. He desires also that God will protect both him and the Thessalonians against the attacks of Satan (3:1-3). He is confident that they will continue to stand firm, and that they will obey the important instructions that he is about to give them (4-5).