If you’ve not read Dan Brown’s The Da Vinci Code, you’re in a shrinking group. More than 7 million hardback copies of the novel are in print, and it has by the publisher’s count been translated into more than 40 languages. It has remained at or near the top of most bestseller lists since its appearance a year ago. The second in a planned trilogy, the novel builds on the characters introduced in Angels and Demons.

The plot involves a quest for the holy grail that begins with a bizarre murder in the Louvre, races through the streets of Paris and the surrounding countryside, and eventually moves to the streets and churches of England. It involves the work of two sleuths: Robert Langdon, a Harvard academic who holds a chair of symbology (the author’s neologism), and Sophie Neveu, a beautiful French cryptologist whose encrypted name means “venue of wisdom.” Brown fills the book with such riddles.

In Leonardo Da Vinci’s paintings the two discover clues to the meaning of the grail. In the end, inevitably, they fall in love. Only then does the reader discover that the grail is not a chalice, as medieval legend has it, but a tomb holding the bones of Mary Magdalene. To make matters more interesting, the grail also represents the womb of Mary Magadalene, who according to the novel bore Jesus’ child and whose descendants live on in France today—Sophie being one of them. For this reason, the mutual attraction between Langdon and Sophie not only creates sexual interest but also holds theological import.

Brown’s novel is a conspiracy tract set in a fictional frame. The conspiracy theory is built on an unorthodox account of Christian history advanced in the early 1980s by the book Holy Blood, Holy Grail. In that pseudo-scholarly publishing sensation, Michael Baigent and colleagues argued, on the basis of documents found in the Bibliothèque de Nationale but later exposed as a hoax, that the descendants of Jesus and Mary Magdalene were part of the Merovingian royal line of the early Middle Ages. The Roman church sought to expunge evidence of this hidden history and eliminate the descendants themselves for the sake of preserving church authority and exalting orthodoxy.

Resisting the power of the church and guarding the secret history of the grail over the years has been a secret society, the Priory of Sion, presided over by a committee of sénéchaux (grand masters). The society engages in a bizarre sex ritual Brown calls Hieros gamos (sacred marriage). Although the meaning of this act remains unclear, it apparently celebrates “the sacred feminine” and embodies the connection between the erotic and the holy expunged by Christianity. Freud would have been pleased to know all this.

The plot thickens through the violent machinations of an albino monk who works for Opus Dei, an actual Roman Catholic organization portrayed by Brown with lightly veiled contempt. A former “British royal historian” named Sir Leigh Teabing, who has devoted his life to finding the grail, also plays a large part in the story.

The book is, of course, fiction. Brown has made it clear, however, that he regards the book as a serious contribution to a revisionist history of early and medieval Christianity, a history that offers insights into the nature of real faith and the identity of the true church. Judging from the enthusiastic response, many readers take him at his word. They find the book fascinating not only because they consider it a good read but also because they discover in it an appealing, alternative reading of Christianity.

The book also presents the Roman Catholic Church as a devious institution marked by deception, violence and scandal. The plot plays on Christianity’s patriarchal excesses and its conflicted approach to sexuality. A few allusions along the way tie this history to the current scandal of priestly sexual abuse and its cover-up. In other words, the book has something for almost everyone unhappy with the church.

The novel also trades on the spiritual hunger prevalent in our day. Brown’s characters frequently excoriate the church for its various atrocities and omissions, and exalt what they see as a lost spiritual aesthetic. “It is the mystery and wonderment that serve our souls, not the Grail itself,” we learn in the book’s waning pages.

Brown’s ambitions as a cultural commentator are not always convincing. Not every reader will warm to the suggestion voiced by one of the characters that we should embrace “orgasm as prayer” and that men’s sexual climax is “a moment of clarity during which God [can] be glimpsed.” In another scene, the novel scolds men for resisting this liberated view of sex, as Langdon reminisces about a lecture he’d recently given to undergraduates: “The next time you find yourself with a woman, look in your heart and see if you can approach sex as a mystical, spiritual act. Challenge yourself to find the spark of divinity that man can only achieve through the sacred feminine.” To which the narrator adds: “The women smiled knowingly, nodding.” Brown clearly intends this as a compliment to women. But the casting of females as sexual partners whose primary role is to help men achieve enlightenment seems an ill-conceived way of honoring “the sacred feminine.” Feminists will not be impressed.

Brown is surely onto something in mingling religion and the erotic, the mysterious and the pleasurable. Such a combination strikes a chord among those who have rarely heard ministers say much on the subject or who assume that Christianity is either opposed to sexual enjoyment or unequipped to deal with it. Brown woos readers who hunger for passion and meaning, enticing them with a vision that unites sexuality and spirituality. It’s certainly a package that sells.

In any case, many women—and, according to Brown’s claim on his Web site, particularly nuns—purport to find this novel profoundly meaningful. Readers have warmed to the author’s efforts to envision a religion more deeply committed to women’s experience and leadership than the one they have encountered in church. Mary Magdalene, he contends, was a leader in the early church—a fact that the church quickly acted to suppress. The real story that Christianity has covered up is not about Jesus at all but about this woman and her (female) descendants. According to the novel, men rewrote the narrative to defend patriarchy and deny the truth of this matriarchal lineage. For many people, apparently, such claims are entirely plausible.

Brown’s defense of this “history” gives fresh meaning to the old cliché about “blind faith.” In an interview on NBC’s Today Show, for example, when Matt Lauer asked Brown if he had based the novel on “things that actually occurred,” the author answered: “Absolutely all of it. Obviously . . . Robert Langdon is fictional, but all of the art, architecture, secret rituals, secret societies, all of that is historical fact.”

On the contrary. The novel relies on slipshod scholarship and mixes occasional fact with a large measure of fantasy. There are, of course, undisputed facts in the novel. Paris does have a Ritz Hotel. The Louvre does display Leonardo’s Mona Lisa. Westminster Abbey is in London. The quest for the grail—the chalice used at the Last Supper— was a consuming fascination in medieval culture. Opus Dei does exist, and the Vatican is located in the heart of Rome. Beyond such matters, almost everything Brown asserts or implies as fact is misleading or mistaken. Mostly the latter.

Some have applauded the book as creating a teaching moment about the contours of Christian history and theology, and thoughtful readers might well be intrigued by complex questions the novel raises about Christian origins. They may also be vexed by the evidence that points to the church’s patriarchal history. Most, however, will have neither the patience nor the knowledge to sort occasional fact from overwhelming fiction.

Among the many errors, confusions and misjudgments is the central claim that the Priory of Sion is of medieval origin, with a list of grand masters that includes Leonardo, his predecessor Botticelli, and the likes of Robert Boyle, Isaac Newton, Victor Hugo and even Claude Debussy. In actuality, this account of the priory first appeared in France in the late 1950s, complete with a fabricated history claiming links to the medieval Knights of the Temple. Brown explains the importance of this connection: “Knights who claimed to be ‘searching for the chalice’ were speaking in code as a way to protect themselves from a Church that had subjugated women, banished the Goddess, burned nonbelievers, and forbidden the pagan reverence for the sacred feminine.” Some of these indictments of the church arise from the legacy of medieval patriarchy. But by feminizing the Templars, Brown turns the plot into a sentimental fantasy. Perhaps he has read too much Sir Walter Scott or fallen under the spell of Camelot.

When Brown refers to heinous facts of church history, he either gets them wrong or magnifies them out of proportion. An example of the latter is his assertion that the church burned 5 million women at the stake during the witch-hunts of the later Middle Ages. If the historical record included only one such murder, it would be too many, but the figure Brown offers would have depopulated Europe altogether during this period. Historians with no interest in protecting Christianity have set the number far lower—between 30,000 and 50,000. Miscalculating by a factor of 100 is understandable to make a point, perhaps, but not when such information is passed along as factual.

A greater muddle is Brown’s attempt to narrate Christian origins. He contends that the emperor Constantine is responsible for much theological mischief. For the first three centuries, he asserts, Christians viewed Jesus “as a mortal prophet, a great and powerful man, but a man nonetheless.” This would have surprised the apostle Paul and most of the theologians whose works defined Christian orthodoxy before the council at Nicea in 325 CE. All shared a belief in Jesus’ divinity, even if they sometimes described it differently.

Brown insists it was Constantine who “upgraded Jesus’ status” by concocting the notion of his divinity—for political reasons. “Many scholars,” Brown insists through the voice of one of his characters, “claim that the early Church literally stole Jesus from His original followers, hijacking His human message, shrouding it in an impenetrable cloak of divinity, and using it to expand their own power.” Who were these early followers interested only in Jesus the man, the great prophet, the human teacher? Brown does not say, and the historical evidence for the claim is nonexistent.

One of the book’s more ridiculous assertions is that the so-called Sangreal documents, held by the Priory of Sion, include “the legendary ‘Q’ Document,” which “even the Vatican admits . . . exists.” A document collecting sayings by Jesus, referred to by biblical scholars by this name, has long been posited as a source for the Gospel writers. But the possible existence of such a document does not justify Brown’s excited tone.

In the category of the bizarre is Brown’s claim that “any gospels that described the earthly aspects of Jesus’ life had to be omitted from the Bible.” What aspects would these be—his teaching, his acts of compassion toward the sick, his care for his followers? One can only conclude that Brown has not bothered to read Matthew, Mark, Luke and John, since these canonical Gospels are persistently and profoundly interested in earthly details.

One of the book’s embarrassing confusions is the notion that the Gnostic Gospels were excluded from the canon because they “speak of Christ’s ministry in very human terms.” In fact, such texts, most of which date no earlier than the late second century, favor an extreme dualism between spirit and body and offer little consolation for those hoping to celebrate the sexual passions that are so much on Brown’s mind. They are largely collections of secret sayings, many bearing references that will strike modern readers as surreal at best.

The noncanonical Gospel of Philip is an example. It does contain a passage—much discussed by scholars—describing Mary Magdalene as the one whom Jesus loved “more than the disciples,” so much so that he used to “kiss her [often],” to the dismay of the men. To read this as a veiled reference to marriage is as flimsy as claiming that Judas’s kiss was really about something other than betrayal.

Further, if this gospel needs to be recovered as authoritative, as Brown insists, then what about its assertion, a few passages later, that “God is a man-eater, and for this reason people are [sacrificed] to him”? Or that “the world is a corpse-eater” and “truth is a life-eater”? Brown seems unaware that the duality of Gnostic cosmology portrays the “flesh” and its appetites consistently in derogatory tones. So much for sacred sex.

In the category of the absurd is Brown’s assertion that references to the marriage of Mary Magdalene and Jesus “kept recurring in the gospels.” Exactly which gospels he is referring to remains unclear. When he goes on to claim this as “a matter of historical record” and to contend that “[Leonardo] Da Vinci was certainly aware of that fact,” one can only wonder what “record” he is referring to. It is unlikely that mention of any such marriage would be found in Gnostic sources, since these generally despise sex because it requires the use of the body.

And what of Brown’s claim that Leonardo’s “Last Supper practically shouts at the viewer that Jesus and Magdalene were a pair”? Brown insists that the effeminate figure at Jesus’ right hand in this scene is Mary Magdalene, not, as tradition has it, “the beloved disciple.” To make such a claim he conveniently ignores the iconographical conventions of the day, which directed that the male disciple described in John’s Gospel as the one whom “Jesus loved” be depicted in just such a manner. The late Renaissance was interested in the affection between older and younger men, not in a heterosexual liaison between Jesus and Mary Magdalene.

Art historians with nothing to win or lose from assessing Brown’s elaborate theories about the “code” in Leonardo’s paintings have largely dismissed his specific claims as well as his overarching theory. Ironically, while Brown celebrates Leonardo’s creativity, he views art primarily as a useful way of concealing information. In Brown’s hands, Leonardo disappears as a masterly artist and becomes little more than a technician inserting esoteric secrets on his canvases. One can already imagine crowds of American tourists lining up this summer, novel in hand, to scrutinize the paintings cited in Brown’s book. So much for art.

Among the ridiculous claims Brown forwards is that “the Church”—by which he means the “sinister” forces of Opus Dei and the Vatican—is bent on destroying the “Sangreal documents” by any means, including violence, because they allegedly reveal the secret truths about Jesus’ marriage to Mary Magdalene and disclose the grail’s true identity. All this is to be explained, according to Brown’s fiction and those who earlier advanced the conspiracy theory, because such documents if ever released would destroy the church’s credibility.

All of this is to say that The Da Vinci Code is based on manifestly bad history and driven by ideological passions. As a novel it also invites readers to an indulgence: it offers a taste of adventure, a glance at art history and a sip of “sacred sexuality” in the form of spirituality lite.

Chesterton once suggested that the saint needed by each culture is the one who contradicts it the most. Brown’s Magdalene and Jesus fail us on this point. His religion of the grail requires no discipline of thought, no virtue in act and little in the category of spiritual commitment.

By contrast, the old-fashioned Jesus of the canonical Gospels stands with the ancient prophets to condemn the misuse of power, the failing of community and the pretension of religion. He calls us to a costly love for the sake of the vulnerable, the oppressed and the marginalized. He summons us to the worship not of a womb or even of a tomb but of the God of justice who exposes the idolatrous worship of nation and power. About such real conspiracies against the faith, Brown remains silent.