

Large audiences are showing up for Da Vinci Code lectures and sermons. More than 10 books are being released, most in April and May, with titles that promise to break, crack, unlock or decode ''The Da Vinci Code.'' Churches are offering pamphlets and study guides for readers who may have been prompted by the novel to question their faith. Word that the director Ron Howard is making a movie based on the book has intensified the critics' urgency. In 13 months, readers have bought more than six million copies of the book, a historical thriller that claims Christianity was founded on a cover-up - that the church has conspired for centuries to hide evidence that Jesus was a mere mortal, married Mary Magdalene and had children whose descendants live in France. Fearing that the best-selling novel ''The Da Vinci Code'' may be sowing doubt about basic Christian beliefs, a host of Christian churches, clergy members and Bible scholars are rushing to rebut it.
