"What on earth is that?" asked Father Brown, and stood still.

"Oh, a new religion," said Flambeau, laughing; "one of those new religions that forgive your sins by saying you never had any. Rather like Christian Science, I should think. The fact is that a fellow calling himself Kalon (I don't know what his name is, except that it can't be that) has taken the flat just above me. I have two lady type-writers underneath me, and this enthusiastic old humbug on top. He calls himself the New Priest of Apollo, and he worships the sun."

"Let him look out," said Father Brown. "The sun was the cruelest of all the gods. But what does that monstrous eye mean?"

"As I understand it, it is a theory of theirs," answered Flambeau, "that a man can endure anything if his mind is quite steady. Their two great symbols are the sun and the open eye; for they say that if a man were really healthy he could stare at the sun."

"If a man were really healthy," said Father Brown, "he would not bother to stare at it."

"Well, that's all I can tell you about the new religion," went on Flambeau carelessly. "It claims, of course, that it can cure all physical diseases."

"Can it cure the one spiritual disease?" asked Father Brown, with a serious curiosity.

"And what is the one spiritual disease?" asked Flambeau, smiling.

"Oh, thinking one is quite well," said his friend.

-The Innocence of Father Brown (1911)

...there is this about such evil, that it opens door after door in hell, and always into smaller and smaller chambers. This is the real case against crime, that a man does not become wilder and wilder, but only meaner and meaner.

-The Innocence of Father Brown (1911)

It seemed somehow that politicians were very important. And yet, anything seemed important about them except their politics.

-The Innocence of Father Brown (1911)

"How in blazes do you know all these horrors?" cried Flambeau.

The shadow of a smile crossed the round, simple face of his clerical opponent.

"Oh, by being a celibate simpleton, I suppose," he said. "Has it never struck you that a man who does next to nothing but hear men's real sins is not likely to be wholly unaware of human evil? But, as a matter of fact, another part of my trade, too, made me sure you weren't a priest."

"What?" asked the thief, almost gaping.

"You attacked reason," said Father Brown. "It's bad theology."

-The Innocence of Father Brown (1911)

Humility is the mother of giants. One sees great things from the valley; only small things from the peak.

-The Innocence of Father Brown (1911)

A waiter came swiftly along the room, and then stopped dead. His stoppage was as silent as his tread; but all those vague and kindly gentlemen were so used to the utter smoothness of the unseen machinery which surrounded and supported their lives, that a waiter doing anything unexpected was a start and a jar. They felt as you and I would feel if the inanimate world disobeyed-- if a chair ran away from us.

 The waiter stood staring a few seconds, while there deepened on every face at table a strange shame which is wholly the product of our time. It is the combination of modern humanitarianism with the horrible modern abyss between the souls of the rich and poor. A genuine historic aristocrat would have thrown things at the waiter, beginning with empty bottles, and very probably ending with money. A genuine democrat would have asked him, with comrade-like clearness of speech, what the devil he was doing. But these modern plutocrats could not bear a poor man near to them, either as a slave or as a friend. That something had gone wrong with the servants was merely a dull, hot embarrassment. They did not want to be brutal, and they dreaded the need to be benevolent. They wanted the thing, whatever it was, to be over. It was over. The waiter, after standing for some seconds rigid, like a cataleptic, turned round and ran madly out of the room.

-The Innocence of Father Brown (1911)

"Where does a wise man hide a leaf?"

"Where does a wise man hide a pebble?"

 And the tall man answered in a low voice: "On the beach."

The small man nodded, and after a short silence said: "Where does a wise man hide a leaf?"

And the other answered: "In the forest."

-The Innocence of Father Brown (1911)

"A Twitch Upon the Thread"

Book Two of Evelyn Waugh's novel Brideshead Revisited is titled "A Twitch Upon the Thread", and is taken from one of GKC's Father Brown stories.

To quote from the novel:

"Still trying to convert me, Cordelia?"

"Oh, no. That's all over, too. D'you know what papa said when he became a Catholic? Mummy told me once. He said to her: 'You have brought back my family to the faith of their ancestors.' Pompous, you know. It takes people different ways. Anyhow, the family haven't been very constant, have they? There's him gone and Sebastian gone and Julia gone. But God won't let them go for long, you know. I wonder if you remember the story mummy read us the evening Sebastian first got drunk – I mean the bad evening. "Father Brown" said something like 'I caught him' (the thief) 'with an unseen hook and an invisible line which is long enough to let him wander to the ends of the world and still to bring him back with a twitch upon the thread.' "

Or, to quote from the Father Brown story itself that is made reference to ("The Queer Feet")

"I am a man...and therefore have all devils in my heart"

"How do you know all this?" he cried. "Are you a devil?"

"I am a man," answered Father Brown gravely; "and therefore have all devils in my heart.

-The Innocence of Father Brown (1911)

"Because silver is sometimes more valuable than gold," said the priest mildly; "that is, in large quantities."

Speaking of the Father Brown Story "The Queer Feet", which I mentioned just recently in connection with the Master's Jacket...Here is a quote from that story.

Father Brown's figure remained quite dark and still; but in that instant he had lost his head. His head was always most valuable when he had lost it. In such moments he put two and two together and made four million. Often the Catholic Church (which is wedded to common sense) did not approve of it. Often he did not approve of it himself. But it was real inspiration--important at rare crises--when whosoever shall lose his head the same shall save it. "I think, sir," he said civilly, "that you have some silver in your pocket." The tall gentleman stared. "Hang it," he cried, "if I choose to give you gold, why should you complain?" "Because silver is sometimes more valuable than gold," said the priest mildly; "that is, in large quantities."

-The Innocence of Father Brown (1911)