He had sinned mortally not once but many times and he knew that, while he stood in danger of eternal damnation for the first sin alone, by every succeeding sin he multiplied his guilt and his punishment. His days and works and thoughts could make no atonement for him, the fountains of sanctifying grace having ceased to refresh his soul.
That's what I thought, too," he said at last, "when I was your age. If there's just one kind of folks, why can't they get along with each other? If they're all alike, why do they go out of their way to despise each other? Scout, I think I'm beginning to understand something. I think I'm beginning to understand why Boo Radley's stayed shut up in the house all this time. . .it's because he want's to stay inside.