NEW YORK — 

It's not just a book.

Back in the 1450s, when the Bible became the first major work printed in Europe with moveable metal type, Johannes Gutenberg was a man with a plan.

The German inventor decided to make the most of his new technology — the movable-type printing press — by producing an unprecedented version of the scripture for wealthy customers who could interpret Latin: leaders of the Catholic Church.

Though he planned on printing 150 Bibles, increasing demand motivated him to produce 30 extra copies, which led to a total of 180. Currently known as the "Gutenberg Bibles," around 48 complete copies are preserved.

None is known to be kept in private hands. Among those in the United States, a paper Bible can be seen at the Morgan Library & Museum, in New York City. Two more copies in vellum lie in the underground vaults, next to 120,000 other books.

Why should anyone — religiously observant or not — feel compelled to see a Gutenberg Bible up close? Here's a look at how its printing influenced the history of books and the religious landscape. And what a 500-year-old volume can still reveal.

What is a Gutenberg Bible?

The term refers to each of the two-volume Bibles printed in Gutenberg's workshop around 1454.

Before that, all existing Bibles were copied by hand. The process could take up to a year, said John McQuillen, associate curator at the Morgan Library. In contrast, it is believed that Gutenberg completed his work in about six months.

Each Gutenberg Bible has nearly 1,300 pages and weighs around 60 pounds. It's written in Latin and printed in double columns, with 42 lines per page.

Most were printed on paper. A few others on animal skin.

When a Bible came off the press, only the black letters were printed. Hand decorations and bindings were added later, depending on each buyer's taste and budget.

Some ornamentations were added in Germany. Others in France, Belgium or Spain.

Therefore, each Gutenberg Bible is unique, McQuillen said.

Why were these Bibles a turning point?

Gutenberg's invention produced a massive multiplication of complete copies of biblical texts.

The first impact was among scholars and learned priests who had easier access than ever before, said Richard Rex, professor of Reformation History from the University of Cambridge.

"This massive multiplication even led to the wider adoption of the term 'Bible' (Biblia) to describe the book," Rex said. "Medieval authors and others do speak sometimes of 'the Bible', but more commonly of 'scripture.'"

Psychologically, Rex said, the appearance of the printed text — its regularity, precision and uniformity — contributed to a tendency to resolve theological arguments by reference to the biblical text alone.

Later on, the printing of Bibles in vernacular languages — especially from Luther's Bible (early 1520s) and Tyndale's New Testament (mid 1520s) onwards — affected the way that ordinary parishioners related to religion and the clergy.

The limits of literacy still meant that access to the Bible was far from universal. Gradually, though, religious leaders stopped being its main interpreters.

"The phenomenon of lay people questioning or interpreting the biblical text became more common from the 1520s onwards," Rex said. "Although the early Protestant Reformers, such as Luther, emphasized that they did not seek to create an interpretative 'free for all,' this was probably the predictable consequence of their appeal to 'scripture alone.'"

More than a book

Three times per year, a curator from the Morgan Library turns the page of the Gutenberg Bible on display. It's leaves not only tell a tale of scripture, but of those who possessed it.

A few years ago, by studying its handmade initials, McQuillen was the one to figure out the origin of its decoration: a German monastery that no longer exists.

Similarly, in the 2000s, a Japanese researcher found little marks on the surface of the Old Testament's paper copy. Her findings revealed that those leaves were used by Gutenberg's successors for their own edition, printed in 1462.

"For as many times as the Gutenberg Bible have been looked at, it seems like every time a researcher comes in, something new can be discovered," McQuillen said.

"This book has existed for 500 years. Who are the people that have touched it? How can we talk about these personal histories in addition to the greater idea of what printing technology means on a European or global scale?" he said.

Among the thousands of Bibles that J. P. Morgan acquired, owners made various annotations. Individual names, birth dates, details that reflect a personal story.

"A Bible is now sort of a book on the shelf," McQuillen said. "But at one point, this was a very personal object."

"In a museum setting, they become art and a little bit distanced, but we try to break that distance down."

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