It can be, but it doesn't have to be. Movies are a visual medium, there are many ways to get contextual clues out there. Body language, how a character reacts physically to others and to situations, inflections in voice and delivery, lighting and mood set in a scene, lots of ways. And let's not forget how we got on this, it was this holocron business. A plot point found absolutely nowhere in the films. If this plot point was so important to the story, should it not be somewhere in the film?