Let no man deceive you by any means: for that day shall not come, except there come a falling away (646 ἀποστασία apostasia) first (4412 πρῶτον proton), and that man of sin be revealed (601 ἀποκαλύπτω apokalupto), the son of perdition (2 Thess. 2:3) KJV
“First” (4412 πρῶτον proton) indicates a progression[i]:
“Apostasy must first come and the antichrist must first be manifested, 2 Th. 2:3”- Theological Dictionary of the New Testament ( Vol. 6, p. 869). Grand Rapids, MI: Eerdmans.
The Man of Sin Antichrist has two phases, he is “the man of sin” false prophet at the beginning of the end time week, and then he morphs into the Beast “Son of Perdition” or “son of destruction” at midweek, becoming the big mouth Emperor of the Revived Roman Empire Beast (Rev. 13:5).
So the apostasy of the church comes first then “the man of sin” arises in it to lead to even greater apostasy, but at midweek casts off all pretensions of being Christian (or Christ) declaring himself an extraterrestrial and greater than all other gods/extraterrestrials that had seeded the religions of humanity in the past. Then he is the Antichrist, not just denying the Father and the Son, he denies the very definition of God as infinite and almighty creator, and opposes all called God while exalting himself above them all.
So the titles “man of sin” and “son of destruction” are not parallel, they mean different things entirely.
The revelation of Antichrist exhibits itself, therefore, as an aping of the appearing of Christ. What in the Redeemer was a profound substantial truth appears in Antichrist as a caricature counterfeit, as, generally, evil prolongs its existence only by aping the good. Thus the Fathers had already correctly interpreted, the leading passages from whom Pelt has collected in his Commentary. (In both phrases it is to be presumed passages of the Old Testament were in Paul’s mind. Ἄνθρωπος τῆς ἁμαρτίας answers to the Hebrew אִישׁ אָוֶן, Isaiah 55:7; Prov. 6:12, υἱὸς τῆς ἀπωλείας to the יֶלֶד פֶשַׁע, Isaiah 57:4, which the LXX. translate by τέκνον ἀπωλείας. The reading of the Codex B. and some MSS. of less authority, ἀνομίας for ἁμαρτίας is, we may suppose, only come into the text here from ver. 7.) Proceeding in the delineation of Antichrist, Paul further names him ὁ ἀντικείμενος, where the article is again to be remarked. Although the LXX., in Zechar. 3:1, put ἀντικείμενος for שָׂטָן, yet Antichrist cannot here signify Satan directly, because in ver. 9 he is distinguished from him. But he has certainly the disposition and tendency of the devil, viz., resistance to God, and to all that is godlike in church and state.- Olshausen, H., Ebrard, J. H. A., & Wiesinger, A. (1857–1859). Biblical Commentary on the New Testament by Dr. Hermann Olshausen. (A. C. Kendrick & D. Fosdick Jr., Trans.) (Vol. 5, pp. 314–315). New York: Sheldon, Blakeman, & Co.
It is religious lawlessness he is guilty of (1 Jn. 3:4), not general lawlessness. That is clear in context which contrasts antichristians led by the “secret power” (NIV) or “mystery of lawlessness” to believe untruth and Christians led by the “mystery of godliness” (1 Ti. 3:16; 2 Th. 2:7-17) God the Holy Spirit who sanctifies the church to believe the truth. These opposing influences are found elsewhere (1 Cor. 12:1-3. 1Ti. 3:16-4:1. 1John 2:18-21; 4:1-6). Confirming “the apostasy” was well discussed in the NT church are the many references to an end time “falling away” from the faith (1Ti. 4:1. 2Ti. 3:1-6; 4:3-4. 2Pt. 2:1-3. Jude 1:4. 1Jn. 2:18-19).
Satan is the Destroyer/Destruction (Rev. 9:11), the antichrist the “son of the destroyer” not only doomed to destruction, as “the Desolator” (Dan. 9:27) he causes destruction, especially of those accepting the mark of his name (Rev. 14:9-11).
The likely sequence is as follows. God removes the restraint of evil above and below (Rev. 9:1). Therefore, when Michael casts out the Devil and his angels they come to earth disguised as Extraterrestrials (Rev. 12:7-12). Its likely they will claim to be “the Designers of life on earth” but that is speculation derived from the presence of such preaching already found on the net. Scripture suggests these will bring a gospel that conquers the world, and it seems to be a parody of Christianity (Rev. 6:2).
A miracle working politician from a small part of the old Roman Empire will rise to prominence, and be accepted into the church as Christ Himself (Mt. 24:24). For the first half of the seven year end time period he will condone sin, teach lawlessness while doing miracles that lie he is from God.
At midweek or 3.5 years, he breaks his covenant with religious people declaring himself above all definitions of God. That is when he morphs into the “Son of Destruction” (Lk. 22:3) who like Judas betrayed the Son (John 17:12). He denies both Father and Son (1 Jn. 2:22; 2 Jn. 1:7) when he opposes all definitions of God (2 Th. 2:4) claiming to be above them all.
[i]3. neuter πρῶτον as adverb, first, at the first;
a. in order of time…first i. e. before something else: Mt. 8:21; Mk. 7:27; 9:11, 12; Lk. 11:38; 14:28; Ro. 15:24; 2 Th. 2:3; 1 Pet. 4:17, etc.-Thayer, J. H. (1889). A Greek-English lexicon of the New Testament: being Grimm’s Wilke’s Clavis Novi Testamenti (p. 555). New York: Harper & Brothers.
Although the πρῶτον καὶ in verse 3 is usually translated simply “first, and,” the translation “first and after it” is preferable for grammatical reasons.16 This suggests that ἀποστασία will occur before the “revealing” of the man of lawlessness.
16. Steve McAvoy cites an impressive array of standard Greek reference works that support the common use of πρῶτον as designating the prior member of a series, and he argues that there is little reason to translate the term here with the sense of “before the Day of the Lord.” He cites Matthew 12:29 and Romans 15:24 as supporting examples (“The Day of the Lord and Certain So-Called ‘Precursors’ ”; http://www.pre-trib.org/data/pdf/McAvoy-TheDayOfTheLordAndCer.pdf [accessed April 2010]). Earl J. Richard comes to similar conclusions (First and Second Thessalonians, Sacra Pagina [Collegeville, MN: Liturgical, 1995], 324).-Dean, D. A. (2011). Does 2 Thessalonians 2:1–3 Exclude the Pretribulational Rapture? Bibliotheca Sacra, 168, 200.
Blue Font emphasis mine.