Factual error: According to the Gospel of Luke (23:28) The sign nailed on top of the cross identifying Jesus as the "king of the Jews" was written in three languages: Greek, Latin and Hebrew. This is confirmed by the Gospel of John (19:20). In the movie the Greek and Hebrew are eliminated from the sign thus giving to the Latin an importance that it did not have for most of the people. This is fixed in the Definitive DVD release.
Continuity mistake: Every shot of Jesus in this film shows him with brown eyes, except one. A shot of Jesus looking up to the sky before he dies, you can see one eye (the one half-shut and bruised) is Jim Caviezel's natural blue.