"I wanted to be loved because I was great. A big man. I'm nothing. Look...the glory around us. Trees...birds. I lived in shame. I dishonored it all and didn't notice the glory. A foolish man..."
This clip ties together some themes that run throughout the film. Here we see Mr. O'Brien living out the end result of pursuing the Way of Nature. He realizes this, and it's breaking him. He's also learned that, like Job, that all his work and good deeds won't prevent misfortune from befalling him.
Jack too comes to a new understanding about himself and his place in the world. He wants to be more like his mother and brother, living in the Way of Grace. But he realizes that he'll constantly be choosing between Nature and Grace, that the two paths as personified by each of his parents will continue to wrestle inside him until the day he dies.