Is Mel Gibson a Sedevacantist and did The Passion contradict the Bible?

To your first question, I believe Mel would claim to be a Sedevacantist, although he is not very outspoken about this. In his interview with ABC he gave the line about how the traditional Mass has “never been abrogated.” This is an argument that non-sedevacantists who accept Paul VI as the Pope make. Regarding the charge that The Passion contradicts scripture, no, I don’t believe The Passion contradicts scripture, except for one glaring change that I noticed that Mel Gibson made to the words of Our Lord. This change was made by Mel to appease the Christ-denying Jews. In the part of the movie where Jesus stands before Pilate (the part that corresponds to John 18:36 ff.), Mel Gibson has Jim Caviezal say:

“My Kingdom is not of this world. If my kingdom were of this world, my servants should certainly strive that I should not be delivered into the hand of this people.”

But Jesus actually said, as recorded in John 18:36:

“My Kingdom is not of this world. If my kingdom were of this world, my servants should certainly strive that I should not be delivered into the hand of THE JEWS.”

Notice the change that Mel made. He changed the words of Our Lord Jesus Christ and His meaning – simply not to offend the Jews. If he had quoted the actual words of Our Lord the scene would have been more powerful and, most importantly, more accurate. This change was striking for me when I saw the movie.