In my recent blogs, I have been presenting the evidence that the Man of Lawlessness prohecy is fulfilled in the first century and that the Man of Lawlessness was Nero Caesar. I noted that he sought worship and opposed God during his rule. But now: How can I explain his destruction by the coming of Christ?
Then that lawless one will be revealed whom the Lord will slay with the breath of His mouth and bring to an end by the appearance of His coming. (2 Thess. 2:8)
As indicated in a previous blog, the lawless one is eventually revealed. The mystery form of his character gives way to a revelation of his lawlessness in Nero’s wicked acts. This occurs after the restrainer (Claudius, who maintained religio licita) is “taken out of the way,” allowing Nero the public stage upon which to act out his horrendous lawlessness.
According to Hendriksen, verse eight destroys the preterist’s identification of the Man of Lawlessness with the Roman emperor, because that verse ties the events to the era of the Second Advent: “The fact is an insurmountable obstacle in the path of the ‘Roman emperor’ theory.” [1} The strong preteristic indications in the passage heretofore, however, demand a different understanding of this destructive coming of Christ.
As I show in the discussion of verse 1, Matthew 24:30 is most relevant here: "Then the sign of the Son of Man will appear in heaven, and then all the tribes of the earth will mourn, and they will see the Son of Man coming on the clouds of heaven with power and great glory." Christ specifically applies that verse to the first century (Matt. 24:34). We may similarly interpret other verses: Revelation 1:7 (cp. Rev. 1:1, 3); Matthew 26:63-65; and Mark 9:1. Christ comes in judgment upon Jerusalem in the A.D. 67-70 events.
In the judgment-coming against Jerusalem there is also judgment for the Man of Lawlessness, Nero. "It is somewhat remarkable that the flames of war consumed almost at the same time the Temple of Jerusalem and the Capitol of Rome."  For the beleaguered Christians there is hope and comfort in the promise of relief from Jewish opposition (2 Thess. 2:15-17) and Nero. Not only does Jerusalem collapse within twenty years, but Nero himself dies a violent death in the midst of the Jewish War (June 8, A.D. 68). His death occurs in the Day of the Lord, which is Christ’s judgment-coming against Jerusalem. Paul tells us that he will die by the breath of Christ. This is like the Old Testament prophecy of the Lord’s destroying Assyria with his coming and the breath of his mouth (Isa. 30:27-31). It is also reminiscent of the language reflecting Babylon’s crushing of Israel (Mic. 1:3-5). In fact, by God’s providence Nero’s death stops the Jewish War briefly so that Christians trapped in Jerusalem can escape (cp. 1 Thess. 1:10). 
 William Hendriksen, I and II Thessalonians (NTC) (Grand Rapids: Baker, 1955), 173.
 Edward Gibbon, The Decline and Fall of the Roman Empire, ed. by Frank C. Bourne (New York: Dell, 1963), 276 (ch. 14).
 See: Josephus Wars 4:11:5. Cp. Luke 21:18, 20-24, 27-28; Eusebius, Ecclesiastical History 3:5:3; Epiphanius, Heresies 29:7. See also: Rev. 7:1-17 in Gentry, Before Jerusalem Fell, 243-244.]. The Man of Lawlessness/Beast, Nero Caesar, dies in the Day of the Lord with the Great Harlot, Jerusalem (Rev. 19:17-21; cf. Rev. 22:6, 10, 12).