He won't play the part of Jesus however. Only direct the movie.
"Mel Gibson is set to direct a movie about Christ's last 12 hours played out entirely in two ancient tongues - Latin and Aramaic - with no subtitles....But Gibson, who turned down Martin Scorsese's offer of playing Jesus, has once again shied away from the role, giving it to Jim Caviezel, star of The Count of Monte Cristo and High Crimes.
"There's two things I wouldn't do on film and I said this when I was in my 20s - I will never play myself if it ever comes to that and I will never play Jesus."