1. Let no one deceive you by any means for that Day (2 Thess 2:1-12)

Some deceive the saints that the Lord has already returned. (2 Thess 2:1-2)

2 Thess 2:1 Now we beseech you, brethren, by the coming of our Lord Jesus Christ, and by our gathering together unto him,
2 That ye be not soon shaken in mind, or be troubled, neither by spirit, nor by word, nor by letter as from us, as that the day of Christ is at hand.

But the Lord comes after the Antichrist appears. (2 Thess 2:3)

2 Thess 2:3 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;

When the Antichrist becomes active, he will entice people with great power to prevent them from hearing the gospel that Jesus is the Christ. (2 Thess 2:4-10)

2 Thess 2:4 Who opposeth and exalteth himself above all that is called God, or that is worshipped; so that he as God sitteth in the temple of God, shewing himself that he is God.
5 Remember ye not, that, when I was yet with you, I told you these things?
6 And now ye know what withholdeth that he might be revealed in his time.
7 For the mystery of iniquity doth already work: only he who now letteth will let, until he be taken out of the way.
8 And then shall that Wicked be revealed, whom the Lord shall consume with the spirit of his mouth, and shall destroy with the brightness of his coming:
9 Even him, whose coming is after the working of Satan with all power and signs and lying wonders,
10 And with all deceivableness of unrighteousness in them that perish; because they received not the love of the truth, that they might be saved.

Jesus will come and kill the Antichrist. (2 Thess 2:8)

2 Thes 2:8 And then shall that Wicked be revealed, whom the Lord shall consume with the spirit of his mouth, and shall destroy with the brightness of his coming:

And those who do not believe in Jesus as the Christ will be judged. (2 Thess 2:11-12)

2 Thess 2:11 And for this cause God shall send them strong delusion, that they should believe a lie:
12 That they all might be damned who believed not the truth, but had pleasure in unrighteousness.