he who opposes and exalts himself against all that is called God or that is worshiped; so that he sits as God in the temple of God, setting himself up as God.
showing himself that he is God: The fourth sin of the antichrist is that he portrays himself as a god. This son of perdition "showing himself that he is God" (apodiknumi) means he "declares" that he is God. No man can truly show himself to be God; however, throughout history, many have claimed to be God. Even though there is no proof for such a claim, by disguise and deceit they attempt to convince others of this falsehood.