...and, therefore, any modern interpretation is inferential at best and rank speculation at worst. One of the governing exegetical precepts we can (and should) use when endeavoring to understand the antichrist's (not the MoL's) identity is the concept of original understanding. Exegetically speaking, what was written in John's letters was understood by John and meant for the understanding of his original readers (it was not originally intended for readers living two millennia later). This is another reason how and why we know the antichrist was not the Pope (there was no Pope in the first century and the closest approximation of a pope back then would have been James (or Peter, for those of RC persuasion).
2 Thess. 2:1-4 (Webster)
1 Now we beseech you, brethren, by the coming of our Lord Jesus Christ, and by our gathering to 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.
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;
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, showing himself that he is God.
This is all about the "man of sin" (or "man of lawlessness" - the manuscripts are divided, but the meaning is almost identical anyway). His character and what he does are described in verse 4. He opposes God. He exalts himself above God. He sits in the temple of God and claims to be God. So, he is against God and takes God's place.
Anti-Christ means against Christ (who is God) and in the place of Christ, which is exactly what we have in verse 4. Not only that, but he sits in the temple of God (i.e. the professing church), so he is a professing Christian, which rules out 1st C. despots like Caligula or Nero.
In any case, we are told, in verse 2, that the revelation of the man of sin/son of perdition was not imminent (at the time of the letter), that a general apostasy had to happen first (as happened with the advent of the papacy). A little later, we are told that one restraining had to be taken out of the way first, before the man of sin would be revealed. Early Christians knew what this was (the Roman Empire), but Paul did not spell it out in his letter, presumably to give some protection from persecution, should the letter fall into Roman hands.
Jesus would also be the man of Lawfulness (since he obeyed and fulfilled the Law). Yes?
Yes.
By that reasoning any measure opposite of Jesus might be added to the antichrist and, therefore, the antichrist might be assigned an almost endless number of attributes and every non-Christian (and a few Christians) could be made into an/the antichrist.
I can't take this comment seriously. We are not talking about run-of-the-mill sinners; we are talking about the "man of sin", "son of perdition" and "anti-Christ". This is obviously something of unique and exceptional wickedness.