To honor the subject matter of a movie like Paul, Apostle of Christ is to focus primarily on the message, but focusing on the message amounts to shortchanging the dramatic elements of the story. In addition, there's the controversy that is forever attendant whenever various groups offer differing interpretations of a religious text. Then there's also the fact that believers aren't always ready to see their faith and its implications onscreen (as in The Last Temptation of Christ), and the fact that non-believers aren't always ready to see it either (as in The Passion of the Christ). All of this adds up to a significant challenge in making a "Christian movie."
Paul, Apostle of Christ wisely decides to focus on the message, ensuring that it does at least one thing well. Which is to say that, broadly speaking, the film is scripturally accurate but falls flat as a piece of entertainment and a work of art.
It isn't the fault of the actors that there is a serious lack of dramatic tension. Indeed, Jim Caviezel as Luke, James Faulkner (Game of Thrones) as Paul, and Olivier Martinez (Taking Lives) as Mauritius all put in admirable turns, while John Lynch (The Fall) is noteworthy as Aquila.
The only place the low budget shows in Paul, Apostle of Christ is in the fact that most of the film takes place on a few sets, which gives things a somewhat claustrophobic feel. However, at least they are well-built sets, and the exterior shots we do see are excellent as well. These high-quality production values give the film an air of credibility it might otherwise lack.
The movie is essentially the story of the writing of the Book of Acts in the New Testament. We see Luke visit Paul while the latter is imprisoned in Rome, where Luke records Paul's sudden, blinding encounter with God on the road to Damascus and his subsequent conversion to Christianity.
On the one hand, churchgoers will find Paul, Apostle of Christ respectful and even reverent. They will mostly be satisfied with the doctrine conveyed in the film and may appreciate the chance to see an important piece of their history and sacred text on the big screen.
On the other hand, there isn't nearly enough character development or conflict to draw in non-believers. They will likely find the film boring and tedious, tuning out before the theological exposition really gets going.
It is extremely difficult to satisfy all possible viewers with a movie like Paul, Apostle of Christ. Better to concentrate on what you're sure you can do well than try to cast a wider net and fail miserably. And what this film does well is portray the life of Paul the Apostle and the history of the early Christian church in the immediate wake of Jesus' death. With fine production values and able performers, Christian audiences will be impressed and moved by Paul, Apostle of Christ.