(RNS) -- If you stacked all the Bibles sitting in American homes, the tower would rise 29 million feet, nearly 1,000 times the height of Mount Everest.
More than 90 percent of American households own a Bible, and the average family owns three, according to pollsters at the Barna Group.
The American Bible Society hands out 5 million copies of the Good Book each year; 1.5 billion Gideon Bibles wait in hotel rooms worldwide.
Scripture outsells the latest diet fads, murder mysteries and celebrity bios year after year. Evangelical publishers alone sold an estimated 20 million Bibles in recession-battered 2009, raking in about $500 million in sales, according to Michael Covington, information and education director of the Evangelical Christian Publishers Association.
Experts say it's nearly impossible to calculate exactly how many Bibles are sold each year. But one thing is clear: The Good Book is great for business.
"Bibles are in many ways a cash cow," said Phyllis Tickle, a former longtime religion editor at Publishers Weekly. "The Bible is the mainstay of many a publishing program."
However, some Christian scholars wonder whether too much Good News can sometimes be a bad thing, as a major new translation and waves of books marking the 400th anniversary of the venerable King James Bible inundate the market this fall.
The assortment of translations and "niche Bibles" (think, "The Holy Bible: Stock Car Racing Edition") sow confusion and division among Christians, invite ridicule from relativists, and risk reducing God's word into just another personal-shopping preference, the scholars say.
"I think we are drifting more and more to a diverse Babel of translations," said David Lyle Jeffrey, former provost of Baylor University and an expert on biblical translations. Jeffrey believes Americans need a "common Bible" -- a role the King James Version played for centuries -- to communicate the grandeur of Scripture without reducing it to "shopping-center-level" discourse.
"When we have so much diversity we lose our common voice," he said.
"It is in effect moving away from a common membership in the body of Christ into disparate, confusing misrepresentations of the rich wisdom of Scripture, which ought to unify us."
Leland Ryken, an English professor at Wheaton College, a leading evangelical school in Illinois, was more blunt.
"When there is wide divergence among Bible translations, readers have no way of knowing what the original text really says," Ryken said.
"It's like being given four different scores for the same football game, or three contradictory directions for getting to a town in the middle of the state."
Christian publishers, meanwhile, say they have an obligation -- even a divine calling -- to make Scripture ready and readable to as many people as possible.
Despite the Bible's ubiquity, Americans are not necessarily reading or absorbing Scripture, said Paul Franklyn, associate publisher of the Common English Bible, a new translation sponsored by five mainline Protestant publishers.
For example, half of Christians cannot name the four Gospels; a third cannot identify Genesis as the Bible's first book, according to a recent study conducted by the Pew Forum on Religion & Public Life.
The new Common English Bible aims to present an easy-to-read translation from the "theological center," Franklyn said. Its New Testament debuts this fall; the entire Bible is due next year.
Despite the profitability of Bible publishing, penetrating the crowded and competitive market is a "big risk," requiring equal parts scholarship and salesmanship, Franklyn said. The Common English Bible publishers spent $1 million on the translation and will doll out another $3 million to get people to "pay attention" to it, he said.