The Doctor: Can I borrow your horse, please? It's official marshal business.
The Preacher: He's called Joshua. It's from the Bible. It means 'The Deliverer.'
The Doctor: No, he isn't.
The Preacher: What?
The Doctor: I speak horse. He's called Susan. And he wants you to respect his life choices.
Rory Williams: Uh, the sign does say 'keep out.'
The Doctor: I see 'keep out' signs as suggestions more than actual orders. Like 'dry clean only.'
[discussing why someone wants to kill The Doctor in a town that they've only just arrived at. ]
Amy Pond: What does he want? Has he issued some kind of demand?
Isaac: Says he wants us to give him the alien doctor.
Amy Pond: [to The Doctor] But that's you. Why would he want to kill you? Unless he's met you.
Shipboard Computer: Thank you for choosing Abraxas Security Software: incinerating intruders for three centuries.
Amy Pond: What's happened to you, Doctor? When did killing someone become an option?
The Doctor: Jex has to answer for his crimes.
Amy Pond: And what then? Are you going to hunt down everyone who's made a gun, or a bullet, or a bomb?
The Doctor: But they keep coming back, don't you see? Everytime I negotiate, everytime I try to understand. Well, not today. No. Today, I honor the victims first. His, the Master's, the Daleks', all the people who died because of MY mercy!
Amy Pond: See, this is what happens when you travel alone for too long. Well, listen to me, Doctor, we can't be like him. We have to be better than him.
[Amy has just accidentally shot a gun twice while waving it about as she's talking]
Isaac: Everyone who isn't an American, drop your gun!
The Doctor: What happens if someone crosses the line?
Isaac: [throws him a hat with a bullet hole through it]
The Doctor: Well, not a very good shot, then.
Isaac: He was aiming for the hat.
The Doctor: [Incredulous] He shoots people's hats?
Rory Williams: So, what do we do with Jex?
Isaac: "What do we do with him"?
Rory Williams: Yeah. I mean, he's a war criminal.
Isaac: No, he's the guy who saved the town from cholera. The guy who gave us heat and light.
Amy Pond: Look, Jex may be a criminal, and yeah, kinda creepy -...
Kahler-Jex: ...And still in the room.
The Doctor: [to the barmaid] Tea. But the strong stuff. Leave the bag in.
Isaac: [to the Doctor and Jex] You're both good men. You just forget it sometimes.