2 Thessalonians 2:4
4 This 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.
2:4The Book of Daniel tells about a very wicked ruler like this. See Daniel 11:36-39.