Revealing mistake: Have a look at some of the beards (and wigs) in this movie, the facial hair is coming loose on several of the disciples' beards.
Factual error: At the end of the film, Mary Magdalene approaches Jesus just as he has arisen from his tomb, at first shocked that he has arisen. As Jesus is talking to her and motioning with his hands, it is plainly clear that he has no nail marks/stigmata, when he should have. (See John 20: 24-29, where-in the resurrected Jesus shows "Doubting Thomas" the nail prints in his hands.)
Continuity mistake: When the emancipated Barabbas leaves his jail cell, he has a thin beard. Going outside of the prison, Barabbas's beard suddenly appears full and bushy.