The Word says the man of sin is the old nature rising up in the last days as it did in Noahs time. The old nature is the seed of Satan and must be cleansed by The Blood Of Christ!
THE LIE IS THAT MEN HAVE NOT BEEN TAUGHT THE BATTLE IS WON AND FINISHED BY FAITH
Therefore God also gave them up to uncleanness, in the lusts of their hearts, to dishonor their bodies among themselves, who exchanged the truth of God for the lie, and worshiped and served the creature rather than the Creator, who is blessed forever. Amen.
For this reason God gave them up to vile passions. For even their women exchanged the natural use for what is against nature.Likewise also the men, leaving the natural use of the woman, burned in their lust for one another, men with men committing what is shameful, and receiving in themselves the penalty of their error which was due.
And even as they did not like to retain God in their knowledge, God gave them over to a debased mind, to do those things which are not fitting; being filled with all unrighteousness, sexual immorality wickedness, covetousness, maliciousness; full of envy, murder, strife, deceit, evil-mindedness; they are whisperers, backbiters, haters of God, violent, proud, boasters, inventors of evil things, disobedient to parents, undiscerning, untrustworthy, unloving, unforgiving, unmerciful; who, knowing the righteous judgment of God, that those who practice such things are deserving of death, not only do the same but also approve of those who practice them.
2 THESSALONIANS 2
The old nature is the man of sin, who we all must defeat through Jesus Christ victory (We overcome the old nature by The Blood of The Lamb and by the confession from our mouth)
Do you not remember that when I was still with you I told you these things? 6 And now you know what is restraining, that he may be revealed in his own time. For the mystery of lawlessness is already at work; only He who now restrains will do so until He is taken out of the way. And then the lawless one will be revealed, whom the Lord will consume with the breath of His mouth and destroy with the brightness of His coming. The coming of the lawless one is according to the working of Satan, with all power, signs, and lying wonders, and with all unrighteous deception among those who perish, because they did not receive the love of the truth, that they might be saved. And for this reason God will send them strong delusion, that they should believe the lie, that they all may be condemned who did not believe the truth but had pleasure in unrighteousness.