A person.
2 Thessalonians 2:3-10 KJV
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, shewing himself that he is God. [5] Remember ye not, that, when I was yet with you, I told you these things? [6] And now ye know what withholdeth that he might be revealed in his time. [7] For the mystery of iniquity doth already work: only he who now letteth will let, until he be taken out of the way. [8] And then shall that Wicked be revealed, whom the Lord shall consume with the spirit of his mouth, and shall destroy with the brightness of his coming: [9] Even him, whose coming is after the working of Satan with all power and signs and lying wonders, [10] And with all deceivableness of unrighteousness in them that perish; because they received not the love of the truth, that they might be saved.