our gathering together. The apostle is referring here to his previous letter to the Thessalonians, in which he had explained “our gathering together unto Him” and its significance (1 Thessalonians 4:13-17).

day of Christ. Some manuscripts read “the day of the Lord” here, but the meaning would be essentially the same either way. To Paul, “Christ” is “the Lord.”

at hand. There seems to have been someone in the church at Thessalonica who had represented himself as speaking and writing for Paul, but who had actually subverted Paul's teachings about the rapture and the day of the Lord. The Thessalonians had become uncertain as to whether the day of the Lord might already be at hand—that is, now happening. This teaching had been especially convincing because of the persecutions they were experiencing. It was necessary, therefore, for Paul to remind them of what he had taught them and provide further information about these great events.

falling away. The “falling away” (Greek apostasia) has commonly been transliterated as “the apostasy” (the definite article in the Greek indicates Paul had already told them about it), and then assumed to apply to the final great religious apostasy at the end of the age. The context, however, as well as the etymology of the word itself, makes this interpretation unlikely. In this precise form it is used nowhere else in the New Testament, so its meaning must be defined by its context here. It is derived from two Greek words, apo (meaning “away from”) and stasis (meaning “standing”). It thus could properly be rendered “standing away” instead of “falling away.” In Paul's previous letter, he had made no reference whatever to a coming departure from the faith, but he had discussed at length a coming departure from the earth by all believers, when Christ returns to meet them in the air (1 Thessalonians 4:13-18). Thus this “standing away from,” in context, seems to refer to all the raptured believers standing away from the earth, as they stand before their returning Lord when they meet Him in the heavens. Paul here is simply reminding them that the “sudden destruction” that would come upon unbelievers when “the day of the Lord” begins could not happen until the rapture—“the standing-away” from the earth before Christ (note Romans 14:10)—had taken place. The entire context, before and after, fits this understanding of the text better than the idea of the apostasy from the faith. Over the 1950 years since Paul wrote these lines, there have been numerous great apostasies form the faith, and none of these introduced the day of the Lord, although persecuted believers in each case might easily have so interpreted them.

man of sin. “The man of sin” is also called “the son of perdition” because of his being so fully energized and controlled by Satan that he is, in a unique way, the son of the devil. Judas, who was a type of this evil man, was also called “son of perdition” (John 17:12; note also Luke 22:3; John 6:70). The same person is also called “antichrist” (xTerm 2:18), “the prince that shall come” (Daniel 9:26) and various other names, but especially “the Beast” (Revelation 13:1, 18, etc.). According to this verse, his identity will only be revealed after the rapture has taken place (note also 2 Thessalonians 2:7-9). Soon (perhaps immediately) thereafter, the great day of the Lord will begin on earth, while the day of Christ is also under way in the heavens. See notes on 1 Corinthians 3:13-15; notes on Revelation 4:1-11.

he is God. The “son of perdition” will be the leader and icon of the global religion of evolutionary pantheistic humanism, which will finally triumph in the last days. There will be a great amalgamation of religions (“all that is called God”), combining the eastern ethnic pantheistic religions and modern New Age scientific and occult religions with apostate monotheistic religions (including the pseudo-Christian denominations and cults left behind on earth after all true Christians have been removed by the rapture), under the charismatic but despotic reign of this great man who will seem to be the very apex of the age-long process of evolution. This, of course, is essentially the goal of the world's anti-Christian and pseudo-Christian religions today, and they will finally attain it for a brief period in the end-times. This wicked king will be a thoroughgoing humanist, honoring only “the God of forces” (Daniel 11:38), and speaking “great words against the most High” (Daniel 7:25), but he will also “cause craft to prosper in his hand; ... and by peace shall destroy many” (Daniel 8:25). He will make a seven-year treaty with Israel (see on Daniel 9:26-27), re-establishing their temple worship at Jerusalem, but will break that treaty after three and one-half years, and will install his own living image in the temple, proclaiming himself to be the god whom all men must worship (Daniel 11:45; Matthew 24:15; Revelation 13:4-8, 14-15).

ye know what withholdeth. The Thessalonians should have known what was restraining the manifestation of the man of sin. This dread event must await the rapture. The influence of true Christians in the world, both in winning others to Christ and in serving as the “salt of the earth” and “light of the world” (Matthew 5:13-14), is preventing the inevitable, quick decay of the world into the darkness and corruption of global evolutionary humanism. Since these Christians actually are indwelt and guided by God's Holy Spirit, it is the presence of the Holy Spirit Himself in the world that is really preventing the triumphant revelation of the man of sin.

letteth. The Holy Spirit, through the true Church, “letteth” (that is, delays, or hinders) the revelation of the son of perdition. In effect, He will be “taken out of the way” when all those He indwells and guides are caught up to meet the Lord. Of course, since He is omnipresent, He will still be present and working on earth, though not through the Church.

let. The English word “let” is derived from the Old English laetan, which in turn came from the ancient Teutonic. Our modern word “late” is from the same source, the original meaning of laetan being “to make late” or “delay.” Thus, this word, as used in this verse, meant “make late” or “delay.” By a strange permutation of language meanings, it has in more recent times come to mean “permit,” almost the opposite of its original meaning.

spirit of his mouth. The man of sin will finally be triumphant, but only for a brief time. The Lord Jesus Christ, returning soon in power and glory, will destroy him with the Sword of the Spirit proceeding from His mouth (Isaiah 11:4; Revelation 19:15, 20-21).

signs. In these confusing times, many Christians are seeking for “signs and wonders” to bolster their faith. This attitude, however, was rebuked by Christ, when He lamented: “Except ye see signs and wonders, ye will not believe” (John 4:48). The danger of being led thereby into a false occultic pseudo-Christianity is very real, for Satan and his false christs and false prophets are also able to “shew great signs and wonders” (Matthew 24:24). But these are “lying wonders,” intended to deceive men into a false worship.

received not. Those who refused “the truth” (that is, Christ—John 14:6) before the rapture will “perish” under the rule of the man of sin. There will be no second chance after the rapture for any who understood but rejected the gospel before the return of Christ. It is, therefore, desperately urgent for all such people (no doubt especially including Americans, who have had every opportunity to receive Christ), to believe on Christ for salvation before He returns. “Behold, now is the day of salvation” (2 Corinthians 6:2).

believe a lie. There is a definite article here—“the lie.” Those who have refused the truth will be given a strong delusion by God Himself when the man of sin is revealed. They will believe his lie, receive him as the god of this age, then perish with him.

damned. That is, “condemned after judgment.”

believed not the truth. Those who do not believe the truth of the glorious gospel of Christ when they have opportunity in this age, rejecting Him as Creator and Savior, are destined for damnation—that is, eternal punishment in the lake of fire. There will be no opportunity for them to be saved in the tribulation period, for their names will have been blotted out of the book of life (Revelation 3:5; 13:8).

However, there will indeed be a great multitude out of every tribe and nation saved during the tribulation period (Revelation 7:9, 14). These will be men and women who never had a real opportunity to understand and receive the gospel before the rapture, but who will believe (often even suffering martyrdom for their faith) when they read or hear it during this coming time of judgment on earth.

called you. Note the clear order here. God had, in the beginning, chosen these Thessalonian believers to salvation before they were born (2 Thessalonians 2:13). Then, He called them as they heard the gospel, believed the truth, and were sanctified (that is, set apart for Christ) by the Holy Spirit, eventually destined to be glorified in Christ. To accomplish this, the Spirit in a vision first directed Paul to go to Greece to preach the gospel (Acts 16:9), where he eventually reached Thessalonica, and taught them the truth. However, of the many who were “called” as Paul preached and taught, only “some of them believed” (Acts 17:4). Most of his listeners had not been chosen, so resisted the call and refused to believe. As Jesus said: “Many be called, but few chosen” (Matthew 20:16). Such a truth may be difficult to understand, but “we are bound to give thanks” (2 Thessalonians 2:13) with Paul that we, like the Thessalonian believers, have been both chosen and called.

traditions. “Traditions” can be either valuable or harmful, depending on whether or not they support God's Word. Jesus, for example, rebuked the Pharisees on this basis: “Why do ye also transgress the commandment of God by your tradition?” (Matthew 15:3). Paul, on the other hand, encouraged the Thessalonians to keep the traditions they had been taught by him, either verbally or in writing (see also 2 Thessalonians 3:6). For the first twenty years or so of the spread of Christianity, each church needed to carefully and accurately remember what they had been taught orally by the apostles or their prophets, pastors, and teachers, for they did not yet have the New Testament in written form. By this time, however, Paul had written down at least some of his teachings, and the New Testament was beginning to take shape. Eventually, by the time the last apostle died, it would all have been written and circulated among the churches, and there would be no further need for them to be guided by the oral traditions. The corresponding message to us today, therefore, would be to “stand fast, and hold the Scriptures which ye have been taught.”