This movie encompasses every major question humans face in life. What is "sin"? What is "forgiveness"? Are we responsible for our fellow human beings?
The takeaway is this: If you think you see behavior that you can't explain, you haven't dug deep enough-there is ALWAYS a reason people do what they do.
Other than the bits at the beginning and the end that show us an empty modern film set, this is a brilliant film. It is NOT a commentary on a race or a class or a gender as some have complained. Yes, it is set in a particular time in a particular place but it is a commentary on humanity.