Well, at least Ebert, Roeper and even Peter Travers of Rolling Stone gave the film a positive review.
They kept throwing stuff at the wall, seeing what would stick. First, it was anti-semitic. Then, Mel's sanity, heritage,'fringe' beliefs, and motivation were 'suspicious'. Then, it was too violent. Then, it wasn't historically accurate. Then, it was being marketed in some nefarious, under-handed way. Then, it didn't focus enough on other parts of Christ's life. Then, Mel is making money off Christ's crucifixion.
The most current anti-Christian spin: Huge box office receipts are due to churches buying huge quantities of tickets and going to see it over and over.
I pity them. They are lost souls--- hopefully they can stop lying and realize that there is transcendent truth that trumps any and all agendas ("....and the gates of hell shall not prevail against it.")