The Great Falling Away and the Man of Sin
Now, brothers, concerning the coming of our Lord Jesus Christ and our gathering together to Him, we beseech you, not to be quickly shaken from your mind, nor be disturbed, neither by spirit nor by word nor by letter, as if from us, as though the day of Christ has come. Let no one deceive you by any means; for that day will not come unless the falling away comes first, and the man of sin is unveiled, the son of perdition, who opposes and exalts himself above all that is called God, or every object of worship, so that he sits as God in the temple of God, showing himself that he is God.
Do you not remember that while I was still with you, I was telling you these things? And now you know that which is restraining, that he may be revealed in his own time. For the mystery of lawlessness is already at work; only He who now restrains will continue until one arises from out of the midst. And then the lawless one will be unveiled, whom the Lord will consume with the breath of His mouth, and will destroy by the brightness of His coming. The coming of the lawless one is according to the working of Satan, with all power, signs, and lying wonders, 10 and with all deceit of unrighteousness among those who perish, because they did not receive the love of the truth, that they might be saved. 11 And because of this, God will send them a strong delusion, in order for them to believe the lie, 12 so that they all might be damned who did not believe the truth, but delighted in unrighteousness.
Stand Firm
13 But we are obligated to give thanks to God always for you, brothers beloved by the Lord, because God chose you from the beginning for salvation, through sanctification of the Spirit and belief in the truth, 14 to which He called you through our gospel, for the obtaining of the glory of our Lord Jesus Christ. 15 So then, brothers, stand fast and hold to the traditions which you were taught, whether by word or our letter. 16 Now may our Lord Jesus Christ Himself, and our God and Father, who loved us and gave us eternal comfort and a good hope by grace, 17 comfort your hearts and establish you in every good word and work.