Jesus gives a warning against false Christs
and false prophets.

Paul states that when this Man of Sin
(whom is also called the Son of Perdition),
is revealed he will set himself up above
all that is worshiped, and will sit in the
Temple of God and show himself as God.

"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;
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."
2 Thessalonians 2:3-4