Through a Glass Darkly (1961)
David, a writer/less-than-stellar father, returns home from a book tour to spend time with his schizophrenic, recently-released-from-the-mental institution daughter, Karin; Martin, Karin's husband and a giant; and Minus, his unfortunately named son. The characters go for a swim, enjoy a meal together, perform an original stage play, brood, talk about God, talk about love, talk about love and how it relates to God, brood some more, etc. The whole thing is gorgeous, stark, and fascinating. A young man never forgets his first Bergman!
Yes, but how does that relate to the film?: What am I, a Biblical scholar?
Shoot the Piano Player (1960)