How we cite our quotes: (Chapter, Paragraph)
Quote #1
"Language, young Todd," he says, "binds us like prisoners on a chain. Haven't you heard anything from yer church, boy?" And then he says his most familiar preaching. "If one of us falls, we all fall." (1.33)
Here we get a good example of how Aaron is guilt-tripping Todd, feeding him the idea that guilt is a communal thing that you can't get away from. Poor Todd is alone (or so he thought), and his thoughts are invaded by his local preacher who tells him that his personal thoughts are contributing to the "fall" of his whole world. We can see why Todd ends up with a guilt complex.
Quote #2
Aaron's gonna die. [He tried to kill me, he wanted to kill the girl, he's responsible for the ruckus in town, he's gotta be the one who sent the Mayor to the farm and cuz of that he's responsible for Ben and Cillian. He deserves to die. He deserves it.
And I can't bring the knife down to finish the job. (8.77-78)
Once again, Todd's trying to justify killing Aaron. He tells himself that Aaron deserves to die because he's trying to kill them, but there's another part of him that can't bring himself to do the deed. Even though he knows he's justified, he feels guilty about the act of killing someone.
Quote #3
And I have my knife raised over Aaron. One more time, I've got my chance. One more time, I've got my knife raised.
I could do it. No one on New World would blame me. It'd be my right. (8.73)
Todd's confused about having free will and having the "right" to do something. First off, we're all pretty clear on the fact that Todd is allowed to protect himself, even if it means killing Aaron. But he's not sure; he can't decide whether this is something that's justified or not. And he's looking at it like it's a privilege to take another's life—not the fact that it's a matter of protection.