Le duel is Pierre Fresnay's only attempt at directing a movie.And considering the results,he was probably wise not to make another one.
Le duel is entertaining ,if it is not taken literally: it's an incredible melodrama ,probably the only one which features a confession,complete with act of contrition.
Pierre Fresnay liked parts of priests:he was admirable in Monsieur Vincent (by Maurice Cloche) which was a biography of Saint Vincent de Paul.As for the others...
Le défroqué (by Leo Joannon) was an extravaganza where a defrocked priest( Fresnay )made a young seminarian drink the consecrated wine after throwing up in the toilets!
Le duel is another extravaganza where Fresnay plays a priest who is still a man ,in spite of all he says to everyone around.He becomes the "spiritual adviser" of a deserted wife (Yvonne Printemps,Fresnay's wife in real life)whose husband ,an aviator , is a celebrity. Enter the priest's brother, a "heathen" surgeon who confesses his love to the woman (on the Eiffel tower!).But the holy man is not prepared to accept it even when the husband dies in a plane crash:he urges her to leave this world for higher "spiritual" concerns,that is to say to become a nun! Pierre Fresnay even casts Raimu (with whom he played opposite in Pagnol's famous trilogy César/Fanny/Marius) as another priest half missionary half guru (without his Provençal accent).
Source : IMDb