Bresson liked to use non-professional actors. Did he think he would get truth to life? but that's just what you don't get. What you do get is stiff, wide-eyed intensity, uninflected voices, an inability to register emotion.
I keep thinking of Piero della Francesca. There's the same combination of naivete and sophistication- and a stylistic rigor so pure it approaches self-parody. Balthasar is a fresco cyle on the life of a saint (who happens to be a donkey.)
Godard says this movie "contains the world". It certainly covers a lot of ground, but where are the laughs?