So, here's a book. You can find it, maybe, on the discount table of a local bookstore, or through Alibris, Amazon, or one of the other online purveyors of used books. I tend to use abebooks.com, where a mass-market paperback edition is currently listed for $5.50 plus $3.00 shipping—which is too much to pay for Reverend Randollph and the Holy Terror, a 1982 mystery novel by Charles Merrill Smith.

Not that Smith wrote particularly bad mysteries. A Methodist clergyman who achieved some fame with a satirical 1965 book called How to Become a Bishop Without Being Religious, Smith decided to try his hand at popular fiction—and from 1974 until his death in 1986, he produced six volumes about Con Randollph, a former professional quarterback for the Los Angeles Rams who, after retirement, became the pastor of a Protestant church in downtown Chicago. To leaf through any of Smith's mysteries is to discover that they're smoothly written, nicely plotted, and mildly comic.

Unfortunately, it's also to discover that they've grown about as badly dated as anything human can possibly become. The Reverend Randollph stories were enjoyable reading for their time. But here, for example, on Amazon—for $7.99 and free shipping—is our own day's rough equivalent: Katherine Hall Page's 2009 The Body in the Sleigh, the 18th entry in a smoothly written, nicely plotted, and mildly humorous series about Faith Fairchild, a minister's wife and caterer who solves local New England mysteries.

Yes, Page's stories are a lot cozier than Charles Merrill Smith's, and a whole lot more feminine, which makes a difference in the narrowly defined markets into which publishers divide mystery fiction these days. But the books share something, for all that—something that every mystery reader knows, although it's hard to name precisely. A characteristic of unlastingness, perhaps. A sort of perishable quality that signals, from the first page, that this is short-lived, timebound stuff. Not strong enough for the main course, not rich enough for dessert, such books get consumed mostly as snacks. The Body in the Sleigh, like Reverend Randollph and the Holy Terror, is the popcorn of its day.

As it happens, the books are also alike in featuring churches as significant backdrops and clergy as major characters. There's a reason Agatha Christie's first story about her spinster detective Miss Marple was called The Murder at the Vicarage (1930)—a book narrated by the village parson. Almost as long as the genre has existed, the religious have been wandering bemusedly into mystery fiction and crime has been paying its bloody visits to sacred ground, from Silas K. Hocking's 1903 Adventures of Latimer Field, Curate to Kate Charles' 2009 Deep Waters—or from C. L. Pirkis' 1893 "The Redhill Sisterhood" to Emilie Richards' 2010 A Truth For a Truth.

Some things have changed over the years, of course: the uses of technology, the openness about sex, and, notably, the treatment of religion. Where a kind of delicate deference once ruled, popular fiction now seems typically to present churchgoing characters as suspects—thanks, as near as I can tell, to the notion that devotion is pretty suspicious, all by itself, and what's a little homicide on top of religious mania? The quantity of casual anti-Christianity in contemporary mysteries and thrillers is more than a little disturbing, their pages full of duplicitous televangelists, fundamentalist cult leaders, and serial killers enacting complex Catholic rituals. Pick up Henning Mankell's Before the Frost for a good example: a 2005 book that essentially equates all religion with the Jonestown suicides, from a Swedish writer whose worldwide sales are now over thirty million. (One dreads the novelisitc uses to which the news from Norway will be put.) When in doubt about the murderer in an old Agatha Christie story, always guess that it's the doctor. And when in doubt about the murderer in a recent mystery novel, always guess that it's the Christian.

Against that over-easy modern trope of blame-the-believers, however, one has to set the teetering stacks of mysteries with actual clerics starring as the detectives—from Harry Kemelman's superior Rabbi Small series, to Ralph McInerny's pedestrian Sister Mary Teresa stories, and all the way down to the truly awful plots of Donna Fletcher Crow's ongoing Father Antony books. In the 1940s, we had Anthony Boucher's Nine Times Nine and Matthew Head's The Devil in the Bush. In the 1950s, Henri Catalan's Soeur Angéle and the Embarrassed Ladies and C. A. Alington's Gold and Gaiters. In the 1960s, Leonard Holton's Deliver Us from Wolves and Dorothy Salisbury Davis' Where the Dark Streets Go. And on and on, decade after decade, down to our own day.

In recent years, most such books have been forced down into even narrower subcategories. Mystery-novel houses are simultaneously the most acquiescent and the most inflexible of publishers; they're like a sheep farm where all the animals rush to cram themselves into whichever small paddock was just discovered to have some fresh grass in it. Catholic priests and Orthodox rabbis, ex-nuns and clergymen's wives: If an author finds success with one such detective, the next two decades are sure to see the conceit nibbled to death.

So, for example, ever since Isabelle Holland gave us the Reverend Claire Aldington in Death at St Anselm's (1984) and D. M. Greenwood contributed the Deaconess Theodora Braithwaite in Clerical Errors (1991), we've been overwhelmed by Anglican women clergy as detectives. The Reverend Margaret Moon in Aline Templeton's Past Praying For (1996), the Reverend Lily Connor in Michelle Blake's The Tentmaker (1999), and the Reverend Clare Fergusson in Julia Spencer-Fleming's In the Bleak Midwinter (2002)—not to mention the Reverend Kathryn Koerney in Crooked Heart (2002), the Reverend Callie Anson in Evil Intent (2005), and the Reverend Faith Morgan in The Reluctant Detective (2010). Nothing short of an angry butcher is likely to halt the sheepish stampede.

And nothing short of divine intervention has much chance of damming the flood of medieval mysteries that began with the international bestsellerdom of Umberto Eco's The Name of the Rose in 1980: Nicholas Barber, Brother Barnabas, and Brother Bernard—and those are just recent clerical detectives set in the 14th century. Whose names start with the letter B.

The female mystery-solvers in these stories seem to run to a higher class of ecclesiastical titles than the men do, on average, what with Dame Averilla, Prioress Eleanor, Dame Frevisse, Abbess Helewise, Abbess Hildegard, and so on. Lord knows, enough medieval mysteries have now been published to speak of averages—dozens of historical novels set in the Middle Ages, of which only three have detectives who have struck me, personally, as worth following, even in the perishable, transient sense: Ellis Peters' series about the 12th-century Benedictine monk Brother Cadfael, Peter Tremayne's stories about the 7th-century Irish nun Sister Fidelma, and Sharan Newman's books about the 12th-century French novice Catherine LeVendeur.

Of course, for a complete list of religious mysteries, you would also need to catalogue the Renaissance, the Protestant Reformation, the Spanish Colonial era, the Victorian age—all the other historical settings for stories about believing detectives (or, at least, detectives imagined to live in believing times). And don't forget the endless stream of supernaturally tinged evangelical thrillers, from Frank Peretti's The Oath to Dee Henderson's The Truth Seeker. Remember, as well, the annual holiday-themed collections: Santa Clues, Mystery for Christmas, Murder at Christmas, Murder Under the Mistletoe—and those are just a few anthology titles from the early 1990s.

At a guess (exact figures are impossible to find; another peculiar feature of contemporary publishing), perhaps three thousand mysteries and thrillers are printed in English every year. And by my rough survey of Amazon results, nearly a tenth of them touch on religion in some clearly recognizable way. All of which means that, even by a conservative count, mystery readers were confronted with more than two hundred new volumes of religious fiction in 2010. And in 2009. And in 2008 … The genre of God and the Detectives has grown to encompass more than anyone can actually read.

Unless, of course, simply having a few spires in the background and a handful of clerics in the foreground isn't enough to make a piece of fiction genuinely religious. Good writing helps, but the quality of the prose, by itself, won't distinguish the strong work from the perishable, junk-food stuff on which mystery readers feed. Something of a religious theme, something of a theological insight, has to be present as well. Something of God must be woven into the literary fabric, not just embroidered on as decoration.

In that sense, the greatest religious mystery novel ever written remains what it has been for well over a century: Fyodor Dostoyevsky's 1866 Crime and Punishment—except for the fact that it isn't a mystery novel. Not really. Not in any of the ways we actually mean when we speak of the popular, almost pulpy genre. However much it concerns a murderer and a detective, Crime and Punishment is too good, too serious, too thick, and, especially, too early to count.

Oh, Dostoyevsky was influenced by some of the same literary trends that would give birth to the new genre (particularly the effects Charles Dickens achieved with such works as the 1853 Bleak House), and it's common enough, when describing mysteries, to point back to early, pre-genre examples of detection and problem-solving. Dorothy Sayers, for example, uses two stories from the Bible—Daniel's solutions to the puzzles of Susanna and Bel the Dragon—to open the first volume of her 1929 anthology, The Omnibus of Crime: The World's Great Masterpieces of Mystery and Detection. But readers know that such things are found only on the fuzzy edges of mysteries: recipients of a courtesy paid to their stature outside the genre, and most of them violating one or another of the famous Ten Commandments for writers of detective stories that the Catholic priest Ronald Knox inscribed in his preface to Best Detective Stories of 1928-29.

Mystery fiction was born, in truth, a bastard thing: its literary antecedents a little vague and certainly not well married. Praise as much as you like the three small tales that Edgar Allan Poe wrote about Auguste Dupin in the 1840s: "The Murders in the Rue Morgue," "The Mystery of Marie Rogêt," and, most influential of all, "The Purloined Letter." Mention E. T. A. Hoffmann's almost forgotten 1819 proto-mystery "Das Fräulein von Scuderi." Appreciate T. S. Eliot's comment that Wilkie Collins' 1868 The Moonstone was "the first, the longest, and the best of modern English detective novels … in a genre invented by Collins and not by Poe." Give some acknowledgment to Émile Gaboriau's detective Monsieur Lecoq, who first appeared in 1866, and note the critic Julian Symons' claim that the 1863 Notting Hill Mystery was the first full-length detective novel. Still, the simple fact is that not much mystery fiction existed before the late 1880s. We recognize these parents only by looking back from their illegitimate child—whose name, as it happens, was Sherlock Holmes.

What's curious is how little of the genre had the benefit of clergy as it came squalling to birth in the gaslight of the late Victorian and early Edwardian age. For everything from Arthur Conan Doyle's first Holmes story in 1887 through the Golden Age of the whodunit in the 1920s and 1930s, religion is probably best understood simply as the received setting—the given condition, the background radiation—of the fiction. It was a kind of secret de Polichinelle: the thing no one bothers to mention because everyone already knows it.

Take merely the writers who formed the Detection Club in London in 1930, the likes of Agatha Christie and Dorothy Sayers, Ronald Knox and Freeman Wills Crofts, the Baroness Orczy and Anthony Berkeley, G. K. Chesterton (the club's first president) and his friend E. C. Bentley. Explicit faith certainly appears from time to time in their work—in the case of Chesterton's Father Brown stories, it cries to heaven—but, far more often, a Christian worldview (typically in a high Anglican form) is merely taken for granted.

Thus, for example, none of Agatha Christie's eighty detective novels and few of her 160 short stories would fit comfortably in an anthology of religious mysteries. Nonetheless, her fiction presupposes a world of vicars and village parishes, a setting defined by the liturgical calendar and the effects of Christian morality. And why not? Of the 28 founders of the Detection Club, Knox and Victor L. Whitechurch were clergymen, while Sayers and Chesterton were known for their religious writings outside the mystery genre. For that matter, Clemence Dane drew her pseudonym from the name of a London church, and Freeman Wills Crofts and associate member Hugh Walpole were brought up in clerical households. The culture of established Christendom was all around them, and they assumed it in their stories without a tinge of self-consciousness.

Perhaps that's why such older books are sometimes praised by the religious and attacked by the irreligious, for mystery writers nowadays seem to lack the innocence, or the insouciance, to assume a God-haunted world in a piece of light fiction. The clerical elements in the 1936 Case of the Stuttering Bishop begin with the book's title—but who would describe Erle Stanley Gardner as a religious writer or include Perry Mason in an anthology of Christian detectives? Under the pseudonym of Edmund Crispin, the British music critic Bruce Montgomery produced some of the most enjoyable classic detective stories ever written, including a 1945 cathedral-close mystery called Holy Disorders, but his works certainly don't belong in the religious subgenre of murder mysteries. Before his death in 2008, Donald Westlake established himself as the grandmaster of the comic crime caper, and his books use Catholic institutions surprisingly often (see, for example, his 1975 monastic comedy Brothers Keepers), but no sane person would call Westlake a seriously Catholic author.

In other words, even the presence of religion all through the story won't transform a piece of detective fiction into a religious mystery. Even the assumption of a Christian culture, with Christian sins and Christian redemptions, can't provide the missing theme: "Easter Parade," for example (one of Rex Stout's marvelous Nero Wolfe and Archie Goodwin tales), turns on the unwillingness of a character to denounce a suspect on Good Friday, but that's no more to the plot than an assumed cultural fact of the time, like New York's snarled traffic and shouting newsboys.

Which leaves us still with the question of what, without fine distinction or special pleading, constitutes religious mystery fiction.

The answer, alas, is G. K. Chesterton. Look, the best religiously influenced mystery novel ever published is Margery Allingham's The Tiger in the Smoke (1952). Nothing else even comes close.

Except maybe Joel Townsley Rogers' surreal The Red Right Hand (1945), although you have to put a question mark beside any book that's so peculiar it keeps half its readers pinned to their seats in awe while the other half stumbles for the exits in stupefaction. And yes, Graham Greene's Brighton Rock (1938) would qualify, except that it over-qualifies: the mystery elements too obviously devices for other literary and religious ends. John Dickson Carr's The Burning Court (1937) is a terrific locked-room problem with theological implications, but it transforms itself, at the end, into a supernatural investigation that steps outside the genre. The Nine Tailors (1934) has both a church setting and the advantage of being one of Dorothy Sayers' later and thus better-constructed works. (In the book's favor, as well, is the absence of the authorial-wish-fulfillment character Harriet Vane, the love interest of the detective, Lord Peter Wimsey. Beware an author who falls so deeply in love with her fictional hero that she writes herself into the stories in order to have him propose to her. In Latin. Which he does in the 1935 Gaudy Night.)

Actually, once you start looking, you find a good number of religious mystery novels—reasonably lasting ones, stronger than the purely perishable stuff—jostling for the top spots. The work of P. D. James, for example, particularly Death in Holy Orders (2001). Or Ngaio Marsh's Death in Ecstasy (1936). Or The Hymn Tune Mystery (1930), written by an Anglican canon under the pseudonym of George Birmingham—although the peak of that subgenre of cathedral-close mysteries probably belongs to either Michael Gilbert's pleasant Close Quarters (1947) or John Trench's What Rough Beast (1957), a book that, as social commentary on the decline of British civility, is quite possibly the bleakest thing ever allowed into print.

The United States didn't have much in this line during the early days of mystery fiction. Before the triumph of the distinctly American hardboiled detective, most local attempts to match the country-house atmosphere of London's Golden Age writers were simply irritating: England got the charming Agatha Christie; America got the annoying S. S. Van Dine. For a good example of studied eccentricity and self-conscious social class in American mysteries, go back and look at the eponymous detective of the early Ellery Queen stories, which began to appear in 1929. Critics typically name The Lamp of God (1935) as the work that marks Queen's turn to a different kind of fiction, beginning with open acknowledgment of religious themes. But even The Lamp of God has enough of the early tics to make you want to slam it against the wall once or twice a chapter.

Almost thirty years later, Queen would revisit some of this religious ground with a 1964 novel called And on the Eighth Day (which the Jewish science-fiction author Avram Davidson helped write). Most of the old annoyances were gone—the narrative is very much a 1960s one, although set during World War II—and yet And on the Eighth Day palls in its own way: simply too strange in construction and theme to belong on a list of classic religious mysteries. That leaves, however, the deliberate puzzle-play Ellery Queen attempted with biblical imagery in Ten Days Wonder (1948). It's an important book in the genre.

But not a great one. In fact, few of even the best of religious mysteries seem genuinely great books: books you just can't live without, books you can't imagine not having read. And that quickly becomes a problem for readers seeking God among the detectives. Antonia Fraser's Quiet as a Nun (1977) hasn't aged as well as might have been expected. Joseph Telushkin's The Unorthodox Murder of Rabbi Wahl (1986) never quite made the leap up into popular esteem. Paul Anthelme's Catholic play Nos Deux Consciences (1902) has serious plot flaws, however much the Catholic director Alfred Hitchcock tried to fix them when he filmed it as I Confess in 1953. H. C. Bailey was the darkest and possibly the most psychologically profound of the Golden Age authors, and The Bishop's Crime (1940) is among his best works—although it, too, has faded from readers' minds in a way the best books simply don't. The insurance-investigator detective in Ronald Knox's Double Cross Purposes (1937) just isn't religious. The possibly millennium-old Coptic priest in Edward D. Hoch's The Quests of Simon Ark (1984) is too bizarre. The hardboiled ex-nun detective in Lee Harris' The Good Friday Murder (1992) is a psychological impossibility.

All of which forces one back into the meaty embrace of G. K. Chesterton and the inescapable, genre-defining short stories about Father Brown.

There's no getting around Chesterton's enormous virtues as a writer. The trouble is that he also possessed, enormously, the vices that come with those virtues. No one has ever written better at high speed, but (as Garry Wills once remarked) it's meaningless to ask how much greater Chesterton would have been if he had been allowed more time to write, because he was constitutionally incapable of taking more time to write. So, too, the most enjoyable and the most exasperating moments of his prose derive from the same source: the famous Chestertonian insistence on forcing every thought into the grammatical structures of paradox. And then there are the narrative successes and disasters that both result from the patterns—the strange metafictional logic—he imposed on his stories.

Chesterton really does stand alone as an English writer: our one great master of deliberate structure, the closest our literature ever allowed itself to come to the logic-game fiction that Jorge Luis Borges constructed in Spanish. He managed a few genuine, if peculiar, small novels: The Napoleon of Notting Hill (1904), The Man Who Was Thursday (1908). But most of Chesterton's fictional outings, even such ostensible novels as The Flying Inn (1914), are really only linked short stories. Tales of the Long Bow (1925), The Poet and the Lunatics (1929): His plan for a book was typically to take a narrative shape—an idea for the logic of a story—and then write an entire collection of pieces manifesting that shape.

So, for example, Father Brown makes his first appearance in "The Blue Cross," a small, fast-paced story of a gentle Catholic priest who foresees and prevents a crime because long practice in the confessional has given him more insight into human nature than gritty worldliness has gained for criminals and policemen. Think about that device for a moment. It's something like the perfect idea for a paradoxical detective story—all our received notions turned on their head: the innocent proving worldly-wise, and the sophisticated exposed as gullible.

Of course, once having finished the story, Chesterton went on to create an entire book's worth of tales with the same basic structure—the twelve stories that form The Innocence of Father Brown (1911), the first volume about the unremarkable-looking priest whose naiveté makes him a clever detective. "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?" he asks a thief who has posed as a clergyman. "But, as a matter of fact, another part of my trade, too, made me sure you weren't a priest …. You attacked reason. It's bad theology."

In the case of Father Brown, the device wasn't too intrusive, and Chesterton had the sense to vary slightly the overarching logic for each of the five books he wrote about his priest-detective. But to read most of his other story collections— The Man Who Knew Too Much (1922), say, or Four Faultless Felons (1930)—is to feel as though you've been dropped off a cliff after the initial, pattern-setting tale. The Club of Queer Trades (1905) opens with a narrative so tremendous that no one can remember much else in the book. (Read Agatha Christie's inferior 1934 retelling of the story in "The Case of the Discontented Soldier" to see why only Chesterton could get away with being Chesterton; we will never experience another writer like him, thank God.) Similarly, The Paradoxes of Mr. Pond (1937) begins with a tale so fine that Borges himself singled it out for praise—and then the book turns to a second story that barely registers, however much it matches the first story's pattern of deliberate paradox.

Which leaves the Father Brown books as Chesterton's only completely successful collections. Not that all the stories are perfect, but the Chestertonian structure serves them well. They are parallel to one another, in a way few other writers have ever attempted, and over and over again the logic of the story involves a theological observation, usually a very Catholic one, that matches something in the secular world.

Don't mistake this for Thomas Aquinas' analysis of Aristotelian categories, as though Father Brown were merely applying a universal truth to a particular instance. Chesterton may have talked a good Thomistic game—good enough, anyway, that the great neo-Thomist Etienne Gilson praised his 1933 popularization Saint Thomas Aquinas: The Dumb Ox—but he wasn't much of a scholastic philosopher. Not by nature, and not by training. What Chesterton does instead is construct intuitive analogies in his mysteries: Father Brown solves crimes by seeing a pattern in them that matches a pattern he knows from his theological and pastoral training.

Ask yourself: Where would a wise man hide a leaf? In a forest. And where would he hide a corpse? In a war—and thus, in "The Sign of the Broken Sword," Father Brown figures out the mystery of a general who started a battle in order to conceal a murder. In "The Eye of Apollo," he solves, in only a few minutes, the death of a nearly blind young woman who has fallen to her death down an elevator shaft while her cult-leader lover prays to the ancient Greek gods on a public balcony. "These pagan stoics," Father Brown explains at the story's conclusion, "always fail by their strength. There came a crash and a scream down the street, and the priest of Apollo did not start or look round. I did not know what it was. But I knew that he was expecting it."

The only real rival Chesterton has for this kind of thing is the American short-story writer Melville Davisson Post. And not even in all that much of Post's work—just the 22 tales he wrote, between 1911 and 1928, about a detective named Uncle Abner, who rides the hills of Virginia in the years before the Civil War. "I have read St. Paul's epistle on charity," Abner at his most Calvinist says to a sheriff he has caught committing fraud, "and, after long reflection, I am persuaded that there exists a greater thing than charity—a thing of more value to the human family …. Do you know what thing I mean, Smallwood? I will tell you. It is Justice."

"I am in no humor to hear a sermon," the sheriff rightly complains—to which Abner even more rightly responds, "Those who need a sermon are rarely in the humor to hear it." Post loved this kind of interplay: a bit of worldly wisdom trumped by the insight of a believer. When Uncle Abner solves the locked-room puzzle in "The Doomdorf Mystery," his Dr. Watson-like companion Randolph exclaims—in the high, Blackstonian language of 18th-century law—"It is a world filled with the mysterious joinder of accident." "It is a world," Abner corrects him in the higher language of the Bible, "filled with the mysterious justice of God."

The key to all these stories is analogy. Just as Chesterton's Father Brown reasons by pattern-identification, using an arrangement he knows from his religious experience to sort out the disarranged facts of a mystery, so Post's Uncle Abner intuits solutions by applying the patterns of stories and moral connections he has learned from reading the Bible: "But where is the motive?" a local doctor asks, and Abner replies, "In the twenty-first chapter of the Book of Kings."

"The Doomdorf Mystery" remains the most-commonly anthologized of Post's stories, but it is, in truth, more an investigation of God's role in human affairs than a straightforward detective tale—and that may be the best way to understand what Post is aiming for in all his Uncle Abner tales. Randolph disbelieves in divine influence on physical events, the Methodist circuit rider in the story considers prayer a weapon of vengeance, and Doomdorf's childlike mistress pathetically tries to conjure the divine with the sympathetic magic of a voodoo doll. Only Abner sees the right role of God's providence—which is how, at the end, he discerns that Doomdorf's crime of brewing illegal peach liquor has caused the man's own death. And when Randolph asks what law of the State of Virginia they should look to, Abner answers, "It is a statute … of an authority somewhat higher. Mark the language of it: He that killeth with the sword must be killed with the sword."

Perhaps there's something about the form of short stories that encourages this kind of explicitly religious detective reasoning—something that allows the success of Chesterton and Post in small compass but weakens larger forms. It's a basic rule of writing: If your metaphor is more complicated than your metaphorand—if it takes more time to explain the image than it does to explain the thing you're trying to use the image to help understand—then you've gone astray. At book length, analogy hardens into allegory, and allegory just isn't one of the standard devices for mystery fiction. As full novels, the short stories in Uncle Abner, Master of Mysteries would be second-rate editions of Pilgrim's Progress and the tales in The Wisdom of Father Brown would be the poor man's version of the Faerie Queene. Fine books in their way, vastly superior to anything in the mystery genre, but not really what counts as a detective story.

Which may explain why Victor L. Whitechurch's "How the Bishop Kept His Appointment" (1912) and J. S. Fletcher's "The Convict and the Clerics" (1932) are both more complete as religious comedies than Donald Westlake's 1985 nun-filled comic novel Good Behavior, even though Westlake is a much funnier writer and his main character of the sad-sack burglar Dortmunder is much more enjoyable than anything in Whitechurch or Fletcher. And why Robert Hichens' "How Love Came to Professor Guildea" (1900) and Frank Ward's "The Dark Corner" (1958) are both theologically more complex as horror-influenced fiction than Stephen King's 1990 The Stand, even though King's fluid writing has made him the single bestselling horror author of all time, and he himself has described his thousand-page book as a "long tale of dark Christianity."

A good anthology could be built, easily enough, from short mysteries touched by a religious impulse. Ormond Greville's "The Perfect Crime" (1932) is a grim but powerful little tale, and Richard Connell's "Brother Orchid" (1938) proves weightier than the schmaltzy movies made from it. As a mystery, A. H. Z. Carr's "The Trial of John Nobody" (1950) isn't all that great, but as a brief study of popular religious enthusiasm, driven by yellow journalism, it remains a classic. Cyril Hare's "Miss Burnside's Dilemma" (1951) would be hard to leave out—as would, of course, a story or two from both Chesterton and Post.

Personally, I'd probably add into the mix Silas K. Hocking's "The Diamond Pin" (1903) and Thomas Walsh's "Chance After Chance" (1977). Possibly Borges' "Death and the Compass" (1944), although it's a stretch. Certainly Christie's "Sanctuary" (1961) and Alice Scanlan Reach's "In the Confessional" (1962). Yes, all right, a nod toward the medieval setting of Peters' Brother Cadfael: "The Price of Light" (1983), probably. Aldous Huxley's "The Gioconda Smile" (1922) for a bit of eccentricity. James Yaffe's "Mom Remembers" (1968) for something Jewish. M. P. Shiel's "The Dark Lot of One Saul" (1912) for something weird.

And then what? Part of the problem is that few of the best short mystery stories are from recent decades. Agatha Christie's breakthrough—the thing that made her quite possibly the highest-selling author who has ever lived—came when she discovered how to take the Sherlock Holmes formula of the late-Victorian magazine story, at around 5,000 words, and extend it into a book-length mystery of 80,000 words. But no one has accomplished anything similar with the religious-analogy short stories of Chesterton and Post. For that matter, the large popular audiences for any type of short magazine fiction long ago drifted off—preferring, apparently, to read 200,000-word doorstops like the bestselling legal mysteries from John Grisham and Scott Turow. What incentive has anyone to add much to the more modest genre now?

Besides, even setting aside the Christmas-themed collections, plenty of anthologies of the old religious stories have already appeared in print, from the 1989 Murder Most Sacred: Great Catholic Tales of Murder and Suspense to the 2002 Murder Most Catholic: Divine Tales of Profane Crimes. You can find them on used-book tables, here and there, if you look hard enough: Mystery Midrash (1999) and Criminal Kabbalah (2001). Murder in the Vicarage (1991) and Thou Shalt Not Kill (1992). Sins of the Fathers (1996) and Ghosts in the Cloisters (1998). Murder Most Divine (2000) and Unholy Orders (2002).

They're all good, and yet, after a while, the stories in such volumes start to blur. One by one, they seem close to perfect, but, strung together, even the best of them begin to leave an odd taste in the mouth—the faint flavor of failure, the slight sense that they're so good they finally make us realize, for the first time, that they may not be good enough. To read a long run of religious mysteries is to suspect that, even at their peak, such stories do not form a central strand of mystery fiction. Maybe God doesn't go all that well with crime. Maybe detectives aren't the best figures to use for explorations of faith. Maybe good theology weakens mystery, and good mystery injures theology.

But that simply won't do. It's unsatisfying as an account of God and the detectives—and for good reason. The apparently inexhaustible impulse to create religious mysteries has to come from somewhere. One cataloguer of the genre, Philip Grosset, lists 219 different clerical detectives in mainstream mystery fiction—including (just among the Catholic figures) four bishops, 17 nuns, and 42 priests, with Ralph McInerny's Father Dowling, William X. Kienzle's Father Koesler, and Andrew Greeley's Father Ryan only a few of the familiar names. The index to William David Spencer's 1992 critical study Mysterium and Mystery: The Clerical Crime Novel runs over twenty pages—as does the index to Synod of Sleuths: Essays on Judeo-Christian Detective Fiction, an interesting 1990 collection edited by Jon L. Breen and Martin H. Greenberg.

You'd expect theologically inclined critics to have much to say on the topic, and they do. A quick search will reveal a raft of mystery essays in intellectual magazines of a religious bent. Christian Century and Commonweal, Cross Currents and The Tablet: It seems a requirement for religion editors that, once a decade or so, they get a major theologian to opine—in a slightly unbuttoned, down-market sort of way—on how surprisingly theological the insights of popular fiction can be. The British-born evangelical theologian J. I. Packer remains among the most-quoted, if only for the fearlessness with which, back in 1985, he announced in Christianity Today that "these are stories of a kind that would never have existed without the Christian gospel. Culturally, they are Christian fairy tales, with savior heroes and plots that end in what Tolkien called a eucatastrophe—whereby things come right after seeming to go irrevocably wrong."

Of course, the theologians are following a general pattern of intellectuals, who often admit—with a curiously proud humility—that they're just ordinary folk with an ordinary taste for mystery novels. Jacques Barzun's 1971 A Catalogue of Crime: Being a Reader's Guide to the Literature of Mystery, Detection, and Related Genres (written with Wendell Hertig Taylor) may be the classic example, but famous Christian apologists are not far behind: Dorothy Sayers, for example, with her sharp-witted 1946 talk "Aristotle on Detective Fiction," or Ronald Knox's playful 1924 reading of Oedipus Rex as a modern detective story, or Chesterton's clever 1912 column "The Divine Detective."

Still, the central text in all discussions of religion and mysteries comes not from a theologian but from a poet—W. H. Auden, whose Harper's magazine essay "The Guilty Vicarage" appeared in 1948. You can guess its thesis right from the opening words, a quotation from Romans 7:7: "I had not known sin, but by the law." In Auden's reading, mysteries are essentially theological, for they concern, at root, innocence and guilt as states of being—as metaphysical realities. He admits that American hardboiled novels can be works of art, but, at the same time, he declares his preference for the cozier world of British country-house mysteries. Mostly that's because such stories involve not art, as he sees it, but magic: an innocent society—"society in a state of grace"—made guilty by crime and then rendered innocent again by the detective's solution.

Proper mystery novels, in other words, begin in the Garden of Eden. They start with the assumption of what Auden names (borrowing from Henry James) "the Great Good Place." Indeed, that's where hardboiled novels differ, for stories from the likes of Dashiell Hammett and Raymond Chandler begin instead in "the Great Wrong Place," in a world fallen and corrupt. One result is, curiously, that a hardboiled detective can forgive or allow the criminal to escape. But the murderer in a classic Golden Age detective story must be found and executed, just as the sinner must be expelled from Eden.

And that's because the murderer makes everyone in the story a suspect; his crime bleeds guilt on everyone around him, an Adamic sin staining all of humankind. The murder introduces law into the innocent garden with the arrival of the police and the private detective—"I had not known sin, but by the law"—and only after the solution of the mystery, and the social expulsion of the criminal, can the innocent slough off their imputed sin and return to a life of grace.

It's an attractive thesis, marred only by the fact that it's mostly wrong. Auden is on to something, but along the way he manages to misread mysteries and misapply theology, which creates fairly serious problems for an explanation of God and the Detectives. As a start, look again at the mysteries he admires. The world is no Eden for Arthur Conan Doyle. Remember Sherlock Holmes' famous description of the countryside in "The Adventure of the Copper Beeches"? In the city, Holmes observes, "There is no lane so vile that the scream of a tortured child, or the thud of a drunkard's blow, does not beget sympathy and indignation among the neighbors." But out in the country, there are only "lonely houses, each in its own fields, filled for the most part with poor ignorant folk who know little of the law. Think of the deeds of hellish cruelty, the hidden wickedness which may go on, year in, year out, in such places, and none the wiser."

For that matter, neither does society begin with anything like a state of grace in the proto-police procedurals from Freeman Wills Crofts that Auden praised. Croft's Inspector French and the Starvel Tragedy (1927), for instance, opens with a description of a miser so complete that the only wonder is that he hadn't been murdered long before. Nearly all the authors of the Golden Age understood the darkness. Agatha Christie's books are filled with old sins that break open like cysts to leak fresh poison through the social body—read Elephants Can Remember (1972), for a self-conscious example—and her detectives are often found urging their friends and clients not to explore clues about otherwise forgotten crimes. "Let sleeping dogs lie," Miss Marple begs the young woman who comes to her in her final story, the 1976 Sleeping Murder.

More to the point, Auden proves too much. It's not an impossible thesis that all mysteries are fundamentally theological, in both form and matter. J. I. Packer and nearly all the other theologians who've written about the topic have certainly thought so. But the thesis also means that no detective stories are theological.

Not particularly, anyway. Chesterton would be, in this account, merely a kind of Toto, pulling back the curtain to show the mechanism by which the wizard's tricks are done. Or perhaps, in this reading, the role of the clerical detective is to purify the genre—to reach toward its fundamental point, to reveal its true meaning. But that doesn't feel right, either. Who wishes R. Austin Freeman's The Red Thumb Mark (1907) had a vicar as its detective? Who imagines Francis Iles' Before the Fact (1932) should have more churches? Who needs God named in James M. Cain's Double Indemnity (1943)? Or Josephine Tey's The Daughter of Time (1951), or Patricia Highsmith's The Talented Mr. Ripley (1955), or Peter Lovesey's The False Inspector Dew (1982), or any other of the works that appear on standard lists of the greatest mysteries ever written? Theological they may be, for the dialectic of guilt and innocence is essentially theological. But religious they are not, nor ever much wanted to be.

In "The Simple Art of Murder," his 1944 Atlantic Monthly essay defending hardboiled fiction, Raymond Chandler singles out A. A. Milne's The Red House Mystery (1922) as the best—or, rather, the worst—example of all that he despises in the British country-house mysteries of the Golden Age. And he's right; there's a reason we remember Milne as a children's author instead of a mystery writer, for although it sold well, what The Red House Mystery mostly reveals is weak plotting, hackneyed settings, and facile prose. It's an attempt to borrow the light atmosphere of Trent's Last Case (1912) without the cleverness of the comic, genre-defying twist at the end, which made E. C. Bentley's book a classic.

And yet, The Red House Mystery may not be as far from The Big Sleep (1939) as Chandler insisted. Or as Auden imagined, or as innumerable critics have since presupposed. If we fold the two ends of the genre back together, we discover what ought not to be a surprise: They all start with a crime. They open with shots ringing out and bodies falling to the ground. However light or dark the author's picture of the world may be, however cozy or grim the fiction seems, they all begin in a world tainted by mortal sin.

That's where they end, as well. The unity of truth, the deep rationality of the world, is a central theme of Thomistic theology: a Christian claim about the structure of reality. And detective fiction depends on that rationality. It relies on at least the expectation that the mystery can be solved—that there exists a resolution to the puzzle. But the fact of crime remains, as well. Sin endures, and mysteries require murder as one of the conditions for their existence in this world unredeemed and unsaved.

Mystery stories, in other words, see reality in a Christian way—or, better, in a partially Christian way. It's what the Christian worldview would be without Christ: sin without redemption; the Fall without the Resurrection; justice, sometimes, but never mercy. Even in the standard ending of a Golden Age novel—the murderer caught and the story's young people properly paired off in marriage (Agatha Christie loved this way of tying up the threads)—the story can't undo Original Sin. We are left in a fallen world, compelled to take only what happiness we can. Individual injustices may sometimes be righted—Raymond Chandler once described hardboiled detectives as medieval knights battling evils on quests through the dark forests of the world—and rationality will occasionally see through confusion and the lies of a criminal. But society itself cannot be made innocent again or returned to any real state of grace. At root, mystery fiction is like a Stoic ethics hung from a biblical metaphysics. It's a .38 special on a .44 frame, and, yes, that is a kind of theology. But it's a pretty low-rent form: God-haunted, without much God.

Auden wasn't wrong, however, to noodle a little about grace in this context—for the explicit presence (or worry about the absence) of grace is what, at last, distinguishes the best religious mysteries and what marks off the genre from other kinds of mystery fiction. A detective story is religious if it superadds an awareness of redemption to the fallen world assumed by all mysteries. If it sees the chance of God's grace down in a universe of sin.

That's what makes Chesterton's Father Brown and Post's Uncle Abner more than just intuitive detectives who happen to use religiously gained knowledge in their pattern recognition. It's what makes Joel Townsley Rogers' The Red Right Hand so interesting, and P. D. James' Death in Holy Orders seem a thick narrative.

For that matter, it's what makes Margery Allingham's The Tiger in the Smoke the archetypal religious mystery novel, the story to which everyone should look for a model. The book owes more than a little to the thrillers of Graham Greene—those quickly written books he called his "entertainments." Stamboul Train (1932) and The Ministry of Fear (1943) are good examples: popular works that taught two generations of Catholic and High Anglican writers to indulge a kind of Christian moodiness, a brooding sense of original sin, and a not-entirely-happy knowledge of the metaphysical presence of God's moral law.

But as Allingham follows her tiger—Jack Havoc, a former commando on a crime spree as he hunts for a mysterious "treasure"—she sees more than just a world of sin. Oh, she opens her story in the fallen world of "the Smoke," which names for her both the London neighborhood through which Havoc rampages and the moral miasma that stains the city: "The fog slopped over its low houses like a bucketful of cold soup over a row of dirty stoves." And yet, even the tiger who stalks through that smoke is not purely malevolent. "Active evil is more incomprehensible in this two-part-perfect world than active good, and so it ought to be," Allingham wrote in an earlier book, and (as the reviewer David L. Vineyard has usefully noted) grace enters Havoc's murderous story through the conduit of a character named Canon Avril. He is a quiet churchman "with an approach to life which was clear sighted yet slightly off-center," and he tries to convince Havoc that he will eventually be destroyed by his belief that his luck allows him to do whatever he wants: "Evil be thou my Good, that is what you have discovered. It is the only sin which cannot be forgiven because when it is finished with you, you are not there to forgive."

In the end, when his luck at last runs out, Jack Havoc is offered grace one last time in the disappointment of the treasure, which proves not to be what he was seeking. The grace is one he refuses to understand or accept, but it's real nonetheless: a presence in the story, a deepening of the book, a thickening of the narrative. Dostoyevsky would have made it the theme of the whole novel, as he did in The Brothers Karamazov (1880). Graham Greene would have broken it open like an egg, as he tried in The Power and the Glory (1940). But neither of those books is a mystery, in any real sense. And a good thing, too, for they would have been unreadable if they were. The genre will contain only so much seriousness, will support only so much heaviness, before it collapses. If you want to write a genuinely rich, genuinely profound investigation of innocence and guilt, you need to build a different novelistic frame.

Still, the mystery story as a literary form is sturdier than some of its critics admit (notably Edmund Wilson in his famous 1945 attack in The New Yorker, "Who Cares Who Killed Roger Ackroyd?"). Genre fiction will support some weight, and the trick in all its permutations—in spy thrillers, in Westerns, in science fiction, even in pulp romance—is to discover exactly how much. Religion can live in mysteries to a reasonable degree, if the analogy of the supernatural is allowed to superimpose itself on the natural world. God can visit the detectives, if the author has the sense to permit it.

All it takes is a little grace.

Joseph Bottum is the author most recently of The Second Spring: Words into Music, Music into Words (St. Augustine's Press).

Copyright © 2011 by the author or Christianity Today/Books & Culture magazine.
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