These articles come directly from e-mail "studies" from Kenneth Gentry.
In this email article I will provide another installment to my brief study on Paul’s Man of Lawlessness. In this study I will show the case for the Man of Lawlessness being . . . Nero Caesar.
Deception and Falling Away
Paul shows a deep concern regarding the deception (2Th 2:3a). To avoid the deception and to clarify the true beginning of the Day of the Lord upon Jerusalem, Paul informs them that "that Day will not come unless the falling away comes first, and the man of sin is revealed, the son of perdition" (2:3). Before they can say the Day of the Lord "is come," then, they must witness first (see RSV) the falling away and the revelation of the man of lawlessness, who is also called "the son of perdition." (These do not necessarily occur in the chronological order presented, as even dispensationalists admit.  Verse nine is clearly out of order and should occur in the midst of verse eight, if strict chronology were important.)
The word "falling away" is apostasia, which occurs in the New Testament only here and in Acts . Historically, the word can apply to a revolt: either political or religious.  But to which does it refer here? Does it point to a future worldwide apostasy from the Christian faith, as per pessimistic eschatologies? Amillennialist William Hendriksen writes that this teaches that "by and large, the visible Church will forsake the true faith." Dispensationalist Thomas L. Constable comments: "This rebel-lion, which will take place within the professing church, will be a departure from the truth that God has revealed in His Word."  Or does the apostasia refer to a political rebellion of some sort?
I believe that it speaks primarily of the Jewish apostasy/rebellion against Rome. Josephus certainly calls the Jewish War against Rome an apostasia(Josephus, Life 4, 9, 10; J.W. 2:2:7; :4; 7:4:2; 7:6:1). Probably Paul merges the religious and political concepts here, though emphasizing the outbreak of the Jewish War, which results from their apostasy against God (Mt 22:1–7; Lk –44; 1Th –16). The emphasis must be on the revolt against Rome because it is future and datable, whereas the revolt against God is ongoing and cumulative. Such specificity would be necessary to dispel the deception on which Paul is focusing. In conjunction with this final apostasy and Jerusalem’s consequent destruction, Christianity and Judaism are forever separated and both are exposed to Rome’s wrath. 
The "man of lawlessness" is Nero Caesar, who also is the beast of Revelation, as a number of Church Fathers believe.  This passage’s difficulty lies in the fact that Paul "describes the Man of Sin with a certain reserve" (Origen, Celsus ) for fear of incurring "the charge of calumny for having spoken evil of the Roman emperor" (Augustine, City of God ). Paul and his associates had already suffered at the hands of the Thessalonican Jews for "acting contrary to the decrees of Caesar, saying there is another king – Jesus" (Ac 17:7). Wisdom demands discreetness when referring to imperial authority; his recent (1Th ) personal ministry among them allows it: they were to "remember" that while with them he "told [them] these things" (2:5).
Paul clearly implies that something is presently (ca.AD 52) "restraining" (present participle) the man of sin "that he may be revealed in his own time" (2Th 2:6). The man of lawlessness is alive and waiting to be "revealed." This implies that for the time being, Christians could expect at least some protection from the Roman government: the Roman laws regardingreligio licita are currently in Christianity’s favor, while it remains a sect of Judaism. This begins to end after the malevolent Nero ascends the throne, for he begins persecuting Christianity in AD 64. Paul certainly enjoys the protection of Roman law (Ac 18:12ff) and makes important use of it in AD 59 (Ac 25:11–12; 28:19), when he seeks protection from the malignancy of the Jews. He expresses no ill-feelings against Rome when writing Romans 13 in AD 57–59, during the early reign of Nero, the famous Quinquennium Neronis. 
1. Constable, Bible Knowledge Commentary: NT , "2 Thessalonians," 718. Non-dispensationalist Marshall comments: "The argument is difficult to follow, partly because of the way in which Paul tackles the theme in a non-chronological manner." I. Howard, Marshall, 1 and 2 Thessalonians, 185.
2. For political apostasia see the Septuagint at Ezra , 15, 19; Neh ; 6:6. For religious apostasia, see: Septuagint at Jos ; 2Ch 29:19; and 33:19, and in the New Testament at Acts .
3. William Hendriksen, I and II Thessalonians, 170. Constable, "2 Thessalonians," 718.
4. "The destruction of Jerusalem and of its temple marked not the end of the world, but the end of a world. It indicated the final separation of Judaism from Christianity, of the synagogue from the Church . . . which thereby opens up principally to the Gentiles." Feuilett, Johannine Studies, 229–30. "The fall of Jerusalem left a permanent mark on the development of the Church. First and foremost, it meant a violent shift of centre, in which the Church was gradually to lose Palestine, the homeland of Jesus and his disciples, and with Palestine Aramaic-speaking Judaism, including the opportunity of spreading eastwards beyond the Roman Empire into Persia and to the second great centre of Jewry at Babylon." Frend, Martyrdom and Persecution in the Early Church, 133.
5. For example: Augustine, City of God ; Chrysostom cited in Alford, Greek Testament, 2:80. If we are correct in equating him with the beast, we could add: Victorinus,Apocalypse ; Lactantius, On the Death of the Persecutors 2; Sulpicius Severus, Sacred History , 29. See my book, Beast of Revelation.
6. Trajan, Epistle 5; cf. Suetonius, Nero 19. See: Henderson,The Life and Principate of the Emperor Nero, ch. 3.