Parkinson: Father! You in trouble, Father?
Father Brown: I'm disappointed in you, Bert.
Parkinson: I'm sorry, Father, it was just...
Father Brown: Firstly, because you did wrong. Secondly, because you did wrong in the wrong way. Frankly, you are an incompetent thief.
Parkinson: Well, I wouldn't go that far.
Father Brown: I would. You are clearly incapable of earning a dishonest living. Why not experiment with an honest one?

Parkinson: Pardon, me lady, but the awful people are coming up the drive!
Lady Warren: What awful people? It is not my "at home" day.
Father Brown: I think he means the police.

Texan Millionaire: [the Texan approaches Father Brown and Lady Warren as they attempt to spot Flambeau among the bidders] Lady Warren? I am Sam Johnson out of San Antonio, Texas. If isn't often we from Texas get a chance to shake a real, live lady by the hand now!
Lady Warren: It isn't often that we in London have the privilege of of meeting a real, live Texan.
Texan Millionaire: You sure talk like a lady. You know, I've come five thousand miles to buy this set of yours. It'll go well down on my ranch.
Lady Warren: Will it really?
Texan Millionaire: Yeah ma'am. I've got myself a real swell games room. Solid gold poker chips, solid gold checkers, and a solid gold ping pong table.
Lady Warren: With solid gold ping pong balls?
Texan Millionaire: No ma'am. They wouldn't bounce. Well, better get set to rope this steer.
[He goes to his seat]
Lady Warren: I feared for a moment he was going to take my hand back to Texas with him, even though it isn't made of gold.
Father Brown: I doubt if even Flambeau could have invented him.

Lady Warren: [referring to the cross of St. Augustine] It's very beautiful. Is it valuable?
Father Brown: No, not valuable. Priceless.

Lady Warren: What progress have you made?
Father Brown: Looking for a black cat in a coal hole during an eclipse of the sun would be a child's task compared with mine.
Lady Warren: You put me in mind of the child's poem: "As I was walking up the stair, I met a man who wasn't there. He wasn't there again today. I wish that he would go away."
Father Brown: I wish that he would come to stay.

Inspector Valentine: [after failing to commandeer a taxi with a couple kissing in the back] Don't the police in France come before a pair of lovers?
Inspector Dubois: In Paris, on a warm afternoon? I'm afraid not.

Inspector Valentine: [the inspector has just phoned in an all-points bulletin for a stolen milk truck] Your accomplices haven't got a chance. They'll be intercepted within half an hour.
Lady Warren: Half an hour? Then you've time for a glass of sherry.
Inspector Valentine: No thank you.
Lady Warren: Or perhaps a glass of milk? The milkman seems to have left rather a lot today.

Inspector Valentine: Well?
Inspector Dubois: He is going to the wine harvest, and the grape waits for no man.
Inspector Valentine: Nor does Father Brown.

Inspector Valentine: You'd've made things much easier for us both if you'd told us what you know of Flambeau.
Father Brown: I cannot tell you what I do not know. All I know is that he walks upon two legs and his head grows above his shoulders.

Father Brown: Appalling.
Flambeau: An odd word to apply to the finest private collection in the world.
Father Brown: What is appalling is that it is private.
Flambeau: You are the first person to have the privilege of seeing it. Look at my El Greco.
Father Brown: Yours?
Flambeau: Mine.
Father Brown: This, I believe, is yours.
[He hands Flambeau his cigarette case]
Flambeau: Oh. So that's how you traced me. Thank you. I wondered where I'd lost it.
Father Brown: You didn't lose it. I stole it.
Flambeau: We have something in common then.
Father Brown: All men do.