Most Americans say that the Bible is important to them—in fact, 88% own a copy. But polls show that fewer are actually reading it than at any previous time in modern U.S. history. In The Invisible Bestseller: Searching for the Bible in America (Eerdmans, out now), religion journalist Kenneth A. Briggs writes that the Good Book has become “a museum exhibit”—a revered artifact that people mostly leave on the shelf.

“A half a century ago you would have seen much more reference to it in political campaigns and public life in general,” Briggs says. “More colleges and universities had departments of religion, and the Bible was studied to a much greater extent.” Today, by contrast, “even evangelical ministers sometimes don’t do Bible quotations, because their own people don’t know the Bible well enough for them to understand.”

In short, America has experienced a fundamental shift. “For a long time in America, the Bible was the guidebook to life,” Briggs says. “I’m not saying it has to be the source of that orientation now, but when the Bible has been the groundwork and you leave that behind, what takes its place?”

To find out, the veteran of Newsday and the New York Times put his journalism skills to work and went on an investigative road trip, interviewing dozens of people over the course of three years of research and writing. He visited Christian colleges where longtime Bible professors bemoaned the religious illiteracy of today’s students, and he interviewed Christian booksellers about the thousands of versions of the Bible that have flooded the market. (Just because people aren’t reading it doesn’t mean that they aren’t still buying it.)

Briggs, whose other books on the intersections of religion and American culture have included Double Crossed (Doubleday) and Holy Siege (HarperOne), says that Eerdmans aims for its books to appeal equally to scholars and people in the pews. That’s a strategy America needs more of, he notes, because increasingly the latter group knows almost nothing about the Bible.

Biblical fluency was certainly the norm during Briggs’s postwar childhood in central Massachusetts. But he harbors no illusions about that time. The Bible’s ascendancy coincided with the rise of an aggressive capitalism that used the Bible in a “practical, achievement-oriented, largely material approach,” he says. That’s an economic narrative that a deeper engagement with the Bible would complicate, not celebrate. “I think a lot of people are scared to read it, because it confronts our value system,” Briggs says. “I don’t know how you read the Sermon on the Mount and still uphold lots of [basic] American values.”