DE-CODING DA VINCI. THE FACTS BEHIND THE FICTION OF ‘THE DA VINCI CODE’; by Amy Welborn; Our Sunday Visitor Publishing Division, 2004; 224 pp.; paperback; $9.95.

Hold onto your popcorn. “The Da Vinci Code” opens in theaters this month and is sure to generate as much controversy as the very popular book.

Still, some readers may be puzzled at the hubbub. After all, “The Da Vinci Code” (DVC) is fiction, so why is it stirring up debate about the history of Christianity?

If you want an excellent, easy-to-read answer to that question, run, don’t walk, to get a copy of “De-coding Da Vinci.”

In her book, Amy Welborn skillfully uncovers the basic problem with DVC, which is this: The book weaves historical falsehoods into its fictional plot. And the result is a deceptive picture of Christianity.

DVC suggests that the Christian church has been involved in a huge cover-up for centuries. The evidence offered is the Gnostic gospels, which claim that Christ was merely a human being, and that He and Mary Magdalene were married.

Fortunately, Welborn digs into history to find the real truth.

Although the Gnostic gospels are real documents, she points out, their philosophy sharply conflicts with the teachings of Christianity. For example, Gnosticism claims that human beings are imprisoned in material bodies, and the material world is evil.

Welborn also notes that the Church has never covered up the existence of the Gnostic gospels, which didn’t end up in the New Testament for a very good reason.

These accounts, written hundreds of years after Christ’s ministry, clash with the facts in the New Testament narratives, which were written by the apostles, who were eyewitnesses to Jesus’ life.

So there was no big cover-up by the Church, as DVC suggests. On the contrary, the Church, in rejecting the Gnostic accounts, was trying to preserve the truth about Jesus’ life and death.

“Yes, human hands played a role in the establishment of the canon,” Welborn notes, but the decisions were not, as DVC claims, motivated by the desire to hold onto power.

Instead, the decisions were part of the obligation “to ensure that Jesus’ life and message were accurately…preserved for future generations.”

The DVC also claims that followers of Christ did not worship Him as Lord, but instead as a great human teacher. Further, the Council of Nicaea invented the idea of the divinity of Christ in the fourth century.

“Wrong again,” says Welborn.

She shows that Jesus’ claim that He was divine is found in numerous places in the New Testament, and that the letters of Paul also reveal that early Christians worshipped Jesus as fully human and fully divine.

Historically, the Council of Nicaea was convened in 325 A.D. to answer certain heresies that had grown up about Jesus. One was created by Arius, who taught that Jesus was not fully God.

The council, then, did not create a belief in Jesus’ divinity, but rather corrected a distorted belief.

Was Jesus married to Mary Magdalene? DVC claims this is “a matter of historical record.”

But Welborn points out that the best historical records available are the Gospels of Matthew, Mark, Luke and John, which were written just a few decades after Jesus’ death and resurrection.

And none of these mentions Jesus having a wife, or suggests the wife was Mary Magdalene.

Welborn also mentions John Meier’s book, “A Marginal Jew.” In it, Meier argues that other relatives of Jesus were mentioned with frequency in the New Testament, so a wife also would have been.

The DVC also suggests that Mary Magdalene was revered as a goddess among early Christians and that the Church plotted to identify Mary as a prostitute, and thus to demonize her.

Welborn goes back to the Gospels. It is true, she says, that several Marys are mentioned in the Gospels, and readers have at times confused them.

In the Western Church, Magdalene became connected with the story in Luke 7, where a sinful, unnamed woman anointed Jesus’ feet. The Eastern Orthodox Church, however, did not conflate these figures and always treated Mary Magdalene with great honor.

But Brown is wrong, Welborn says, in suggesting, “Mary Magdalene was marginalized and demonized by traditional Christianity” and painted as a wanton woman. In truth, Christianity, both Eastern and Western, has honored Mary Magdalene as a saint. They’ve named churches after her and ascribed miracles to her, Welborn emphasizes.

“How in the world, in what universe, is that demonizing?”

Welborn suggests that so many people have embraced the false claims in DVC because they’ve failed to try to get to know Jesus.

“We’ve stood at a distance from him, letting others tell us what to think about him, never bothering to read even a single Gospel from beginning to end ourselves.”

The result, she says, is that many people believe that Christianity is just an opinion, and all opinions are equal.

But the martyrs who died for their faith “did not give their lives to a metaphor,” she notes. “They gave their lives—literally—to him and the grace-filled, abundant life with which they were filled.”