Washington, D.C. — If you walk through the new eight-floor, 430,000-square-foot Museum of the Bible too quickly, you will miss Steve Green’s favorite object. Mr. Green, the museum’s founder and also the president of Hobby Lobby (plaintiff in the prominent 2014 Supreme Court religious-freedom case), created this half-billion-dollar high-tech shrine to the Bible as a labor of love. But it is a small, plain brown book in the lower corner of a display case on the second floor — the Aitken Bible — that speaks most to Mr. Green.

Robert Aitken’s Bible was the first-known copy to be printed in America. Before the American Revolution, Bibles could only be imported from Europe and required a special license from the Crown. But in 1781, Aitken petitioned Congress to be allowed to publish “a neat Edition of the Holy Scriptures for the use of schools.” The enthusiastic reply read: “The United States in Congress assembled highly approve the pious and laudable undertaking of Mr. Aitken, as subservient to the interest of religion, as well as an influence of the progress of arts in this country, and being satisfied . . . of his care and accuracy in the execution of the work, they recommend this edition of the Bible to the inhabitants of the United States.”

That Aitken put that inscription “right in the front of the Bible,” says Mr. Green, “it tells us a little about the culture during the days of our Founding.” During our conversation on the top floor of the museum — which includes suites where scholars and dignitaries visiting the museum can stay — Mr. Green does not ever say that America is a “Christian nation.” But he is quick to point out that the Bible has strongly influenced the foundation of our politics. “The idea that all men are created equal was a biblical concept,” Mr. Green notes. “We talk about these truths being self evident, but if we don’t know the Scriptures, it may not be self-evident at all.”

And this is Mr. Green’s biggest concern. According to a survey by Lifeway Research in the spring, nine in ten Americans own a Bible, but more than half have read little or none of it. When surveys are conducted on our knowledge of the Bible, the results are abominable. Just a third of Americans can name the four Gospels, and one out of ten think Joan of Arc was Noah’s wife. As Mr. Green observes: “You see Good Samaritan stories on the news. But if you don’t know the Good Samaritan story . . . You lose context if you don’t understand the Bible.”

He doesn’t think the problem is a falloff in religious attendance — “people have access to church on their phone through live Facebook or whatever.” Church is like “a lot of industries [that] are changing because of that digital age,” he tells me. Using new technology to teach old ideas seems to be the goal of the museum, which includes a virtual-reality flight through Washington, D.C., to see quotes from the Bible all over the city, as well as enough touchscreens, movies, and special effects to compete with Disney World.

The museum is not Mr. Green’s first foray into remedying biblical illiteracy. For several years he has supported the development of a curriculum to teach students about the Bible. When the content of the curriculum was leaked early on, critics noted that it presented a Christian interpretation of the stories — the tale of Adam and Eve was presented as the story of the fall from innocence, even though Jews do not believe in original sin. The other main criticism was that the curriculum led students to believe that the Bible is true. For legal reasons, the curriculum was shelved in 2014 by an Oklahoma school district that was planning to adopt it.

Mr. Green’s group went on to develop different curricula — one that is being used in about 150 private schools, and another one for public schools that will be presented next fall. Though Mr. Green says the two are very similar, the former is focused more on the impact of the Bible and less on its history. (Aspects of the curriculum have also been adopted for use by thousands of students in the U.K. as well as in Israel.)

Mr. Green says his experience with the curricula “helped me understand certain limits we have for the museum. I don’t want my child going to public school to be proselytized to by another faith. So I need to be respectful of people of other faiths and not do the same thing.” Perhaps this sounds like false humility, but Mr. Green hardly seems like the narcissistic, theocratic billionaire the media have made him out to be. (“He had the air of a man who knew that people would wait for him,” according to an article in The Atlantic. “He has a political agenda that amounts to civil disobedience against the First Amendment,” according to a law professor at the University of Oklahoma.)

He and his wife, Jackie — high-school sweethearts — still live in Oklahoma City, where they have raised five children. The youngest — an eleven-year-old girl adopted from China — is still at home. Mr. Green and his wife arrive at our interview each towing a roller suitcase, his with a garment bag from Men’s Wearhouse draped over it. When I ask why they didn’t stay in one of the museum’s suites instead of at the nearby Residence Inn, Ms. Green shrugs as if it had never occurred to her.

It is easy to imagine how Hobby Lobby’s challenge to the Affordable Care Act has made the company and the family a target for liberals. In a new book called “The United States of Hobby Lobby,” out this fall from Princeton University Press, theology professors Candida Moss and Joel Baden say that the fact that Mr. Green and his family “believe it is possible to tell the story of the Bible without interpretation betrays not only their Protestant roots and bias, but also their fundamentally anti-intellectual orientation.”

A Southern Baptist whose grandfather was a Pentecostal preacher, Mr. Green acknowledges that his “religious world was fairly small,” mostly restricted to other Protestants. “But as we grew and were exposed to other denominations, my world kind of broadened. And then, with this museum, it exposed me to other faith traditions, which broadened it even further.” The museum has developed partnerships with the Vatican and the Israel Antiquities Authority, which both have dedicated space in the museum to display art and artifacts from their collections.

But Mr. Green has had to do more than expand his religious horizons in recent years. He and his representatives have traveled the world acquiring the $205 million collection of 40,000 artifacts, but some of this has been done incompetently and illegally. Boxes of artifacts were mislabeled and confiscated by customs authorities, and the provenance of some artifacts remains in question. Hobby Lobby had to pay $3 million in July to settle a lawsuit by the U.S. government alleging goods had been smuggled into the country. The theft and illegal sales of artifacts from the Middle East has helped to fund ISIS’s activities around the world, experts say.

Mr. Green has acknowledged his missteps, but he says they were the mistakes of an amateur. “You can’t just look up in the phone book and find experts down the street who know how to advise you on those things.”

Perhaps chastened, Mr. Green is a man who is hesitant to get too far into the weeds on topics that are outside his area of expertise. It has been three years since his company achieved victory at the Supreme Court, earning an exemption from the Affordable Care Act’s mandate that employers provide contraceptive coverage. Mr. Green says he has not followed the details of the similar Masterpiece Cakeshop case currently before the court, but he notes the issues are the same: “There are still challenges to religious freedoms in this country.”

This is certainly one reason, he says, that Evangelicals have stood behind the president even if he doesn’t exemplify the behavior they might be looking for from a public figure. Mr. Green’s father, the CEO of Hobby Lobby, was extremely critical of the president during the primaries — saying Mr. Trump “scares [him] to death.” Today, Mr. Green says of his religious community: “I think that there is probably a kind of a love/hate relationship there. There are, obviously, things that have been very positive towards the faith community that has created a lot of good will and then there are things that he has done that I’m sure they would cringe at.”

Indeed, though he appreciates the president’s support of religious liberty, he seems to distance himself from some of Mr. Trump’s other religious messages. When I ask about the “War on Christmas,” for instance, Mr. Green notes, “There is a certain amount of it that is made up.” Mr. Green thinks that people should feel free to say “Merry Christmas” without worrying about offending others — “it’s part of the culture” — but he also suggests that too much emphasis on these perceived slights is not helpful.

“There are more challenges to the Christian community in America than there used to be,” Mr. Green acknowledges. But he worries about Christians in America thinking of themselves as victims of “persecution.” “It pales in comparison with people in other countries, where owning a Bible . . . may cost them their lives.” If nothing else, Mr. Green’s new venture aims to show the world why.

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