A posttribulationist challenged me that 2 Thessalonians and Revelation 19 refer to the same event, and thereby he believes the rapture will occur at the end Daniel’s 70th week. His main (and only) argument was: “Paul says that we get our rest when Jesus comes in flaming fire. He comes in flaming fire at the end of Daniel 70th week. I just wanted to know if Jesus comes back in flaming fire twice or once?
There is no fire described in Rev 19 with the Battle of Armageddon, only a metaphor of “His eyes are a flame of fire.” In contrast, the beginning of the day of the Lord begins with the rapture (Rev 7) and this is followed immediately by God’s wrath characterized by a lot of fire, which begins with the trumpet judgments:
Then the angel took the censer and filled it with the fire of the altar, and threw it to the earth; and there followed peals of thunder and sounds and flashes of lightning and an earthquake. And the seven angels who had the seven trumpets prepared themselves to sound them. The first sounded, and there came hail and fire, mixed with blood, and they were thrown to the earth; and a third of the earth was burned up, and a third of the trees were burned up, and all the green grass was burned up. The second angel sounded, and something like a great mountain burning with fire was thrown into the sea; and a third of the sea became blood” (Rev 8:5–8)
Also related to this point is the following excerpt from one of my forthcoming books:
Pretribulationist Richard Mayhue thinks that Paul does not teach a back-to-back nature of the rapture and God’s eschatological wrath. He writes,
Paul is not writing a detailed, chronological, or even precise prophetic treatise here, but rather is wanting to give the Thessalonians hope that, in the end, God’s righteousness would prevail. Like Old Testament prophets (cf. Isa 61:1–2; 2 Pet 1:10–11), Paul has compressed the details so that the range of time is not apparent, nor are all of the details. The apostle is plainly assuring the Thessalonians that there will certainly be a coming day of retribution for their persecutors. As a result, this text has no bearing on determining the time of the rapture. (Mayhue, “Why A Pretribulation Rapture?,” 101)
We can agree with Mayhue on two points. First, it is correct that it is not Paul’s intention to write a detailed account of God’s wrath as if it all occurs within a twenty-four hour day. Paul is compressing the details for the purpose to give a summary statement concerning judgment. He is only highlighting the point that on that first day when Christ returns there will be two immediate consequent effects. The saints will be delivered and the wicked begin to be judged. Paul is emphasizing judgment qua judgment and not intending to describe the full account of the unified complex-whole of judgment elements, for example, with the trumpets, bowls, and the eternal lake of fire that we see in the book of Revelation. Second, we can agree with Mayhue that Paul is giving “hope that, in the end, God’s righteousness would prevail” and “assuring the Thessalonians that there will certainly be a coming day of retribution for their persecutors.” We must, however, disagree with Mayhue’s assertion that Paul does not use temporal language. Paul uses explicit temporal language by chronologically tying together deliverance and judgment: “when,” “on that day.” In fact, the “hope” that Paul is seeking to foster for the trepidatious Thessalonians is grounded in the promise that God will begin to judge their persecutors on the same day as the deliverance of the godly! Paul could not describe it more plainly: When Jesus is revealed from heaven “to give rest” to his afflicted people, he will be accompanied “with his mighty angels” and with “flaming fire to mete out punishment” upon the wicked. Thus, Mayhue’s interpretation of Paul is flawed and ignores this key point in Paul’s instruction.
See also the two series on this related point where I elaborate more here and here.