Is it a porno movie? I doubt it. So he is making a movie in which he has to portray a bad guy, or even a non christian. Big deal. It's a MOVIE.
The characters actors portray in movies are a vast difference from how they actually live their lives. He might be able to call upon his life in the past for experience, but it is still a movie. How he lives his real life is more important than the character portrayals he may have in films.
I added (some) to your statement because there are many actors who put their money where their mouths are and will not lend their talent to certain types of projects....and then there are those who put their personal values on the shelf in order to get a pay day.