I’ve tried to research this and I can’t get a simple, straightforward answer. If I watched a R-rated movie with sex or nudity in it, did I commit a mortal sin?
It depends on the movie and your intentions in watching it. Some R-rated movies, such as Schindler’s List, may contain sex and nudity but be appropriate for adult audiences. It is up to the individual adult Catholic to find out as much as he can about the movie through resources like DecentFilms.com and make an informed decision for himself. Of course, if your intention is to seek out titillation by watching an R-rated movie, then even an appropriate R-rated movie like Schindler’s List (or even The Passion of the Christ for that matter) can become an occasion of sin for you.