The Diary of a Country Priest by Georges Bernanos has three prominent themes. The first one is the duality of materialism and spiritual experience. The priest—who sees himself as an intellectual—has a habit of making assumptions about other people, specifically judging whether one is following or not following Christian principles. This is illustrated by his tense relations with a young woman whom he tries to guide towards a more Christian way of living.

The second theme is the devotion to seeking divinity in the material mortal world. The priest is so devoted to his theological pursuits that his physical health deteriorates. The young woman aides him back to health, but it is not enough. When the young priest dies, the scene is reminiscent of Christ's final seconds on the cross, and the priest sees "God's grace" all around him. He believes he has fulfilled his duty as a priest during his short time on Earth.

The other theme is the concept of understanding. This begins with misunderstanding between the priest and those around him, which stems from contradictions of individual personal beliefs. This is evident in his philosophical debate with Chantal. In the end, Chantal is able to see the priest's theological perspective despite deciding that she will do as she wishes. The message of the author is conveyed before the story ends: one must have the courage to carve their own paths in life despite the opinions of others. This is illustrated by both the priest and the young woman, respectively. The priest sticks to his convictions despite almost being fired from his post, and Chantal remains fiercely independent.