Charles Bickford in THE SONG OF BERNADETTE.
Lothaire Bluteau in BLACKROBE.
Loved the scene where he tries to discern Bernadette's understanding of the term "Immaculate Conception" which necessitates his explanation of it to her. After asking her if she understands his explanation and receives a negative response from her, his reply is priceless. Something to the effect, "Why should you? The greatest theologians have racked their brains for centuries over it."