2 Thessalonians 2:3-4

3Do not let anyone deceive you like that in any way. That day will not happen until certain other things have happened. Before that day, there will be a time when many people will turn against God. Also, the man who is completely against God will appear. God will surely destroy him in the end.

4This man will be God's great enemy. He will say that he is greater than everything that people call their gods. He will say that he is greater than everything that people worship. As a result, he will even go into the temple. He will sit down there like a king. He will tell everyone that he himself is God.