The bestselling book of all time is believed to be the Bible, but the holy book is not the only title attracting readers looking for books that reflect Christian values.

Christian publishers produce a variety of fiction novels covering traditional commercial genres — historical, suspense, romance, contemporary — but their readers desire more than a good story.

“Your reader is looking for something consistent with the biblical world view,” says Andrea Doering, editorial director for Revell Books, a division of Baker Publishing Group, one of the dominant Christian publishers in the market. “They are not going to run into language that’s offensive, they’re not going to run into premarital sex being celebrated as a real lifestyle or having affairs as something that is commonplace or OK. It’s not that that doesn’t happen in the plotline, but it’s not considered the best way of living. They want the story, but they don’t want to have to put a filter on.”

The Christian book market accounts for 7 percent of the total book market so far in 2018, earning $44 million, up from $39 million, or about 6 percent of the total book market, last year, according to The NPD Group. Between 2016 and 2017, the Christian market saw a revenue increase of 5 percent.

These steady increases over the past three years have continued despite a decline in Christian book distributors and the shuttering of Family Christian Stores, the largest retailer of Christian books and merchandise in the country, which closed all 240 of its stores in 36 states in 2017, after declaring bankruptcy in 2015.

Nonfiction titles tend to dominate the Christian publishing market. In December 2018, the top five Christian bestsellers were nonfiction, according to The NPD Group.

One of 2018’s overall breakout publishing stars is blogger Rachel Hollis. Her self-help book, Girl Wash Your Face, has sold more than 2 million copies since its publication in February 2018 and has stayed on The New York Times bestseller list for 34 weeks. Hollis’s runaway hit was published by Thomas Nelson, a division of HarperCollins that focuses on providing Christian content.

At Baker Publishing Group, the current bestselling title is a “clean” joke book for kids. Other big moneymakers for the publisher include Manual to Manhood and The Girls’ Guide to Conquering Life, which offer basic tools for living for adolescents.

“Revell publishes books for people with a faith-based background that are looking for hope and help in their everyday life. They’re looking for inspiration. They’re looking for tools to live better,” says Doering. “In all of our fiction even, hope is definitely an element, even in the suspense. You know, the good guy wins, justice is always served. We want to show basically that there is power in the truth and there’s power in the gospel.”

The average Christian book buyer is a woman, about half of Christian book buyers are over the age of 45, and almost half of Christian book-buying households earn less than $50,000, according to a 2015 report released by Nielsen BookScan (which was acquired by The NPD Group in 2017).

On the fiction side, suspense, romantic suspense and romance are among Revell’s bestselling titles, according to Doering. Stories set in America, including in Amish country, have the most appeal to readers.

Certain rules apply in Christian fiction. For example, cursing and premarital sex are big no-no’s.

Author Vanessa Riley, a Stanford graduate with a PhD in mechanical engineering, says she rarely thinks about guidelines when writing her faith-filled historical romances. Her books are influenced by her upbringing in the American South, the so-called Bible Belt, and her own 30-day Christian courtship, during which she met and became engaged to her husband of 22 years.

“As a woman of faith, writing a story of faith, there’s just things that you’re just not going to do,” Riley says. “If you have an inground faith, if you have a passion to tell a story that’s going to edify the soul and make people think that there’s hope, you don’t really need a list of this, that and the other thing to make sure your stories fit.”

Riley, whose historical romances feature multicultural characters, has been published by both mainstream and Christian publishers, but she says it’s been a challenge to find a home for her stories in the Christian publishing world.

“I think that the inspirational market as is, is telling very similar stories to what they’ve always told and I think there is a definite market for that,” Riley says. “If they want to diversify their readership so they look like more of middle America, the urban cities, the South as we see it every day, then they’re going to have to look for more stories and I think that’s their quandary. They don’t know how to tap into these other markets.”

Doering, who has not worked with Riley, says she welcomes all kinds of characters.

“If someone positions a book as ‘This would be great to add to your multicultural or your diversity landscape,’ I would say, ‘Well, you tell me a great story and then let’s talk.’ That’s the key. For a reader, it’s all about the story.”

Although author Shawn Smucker is the son of a pastor, he says he didn’t set out to write overtly religious books, yet his young adult mysteries do reflect his Christian values. When his agent tried to sell his first book, Smucker ran into obstacles from both mainstream and Christian publishers.

“Most of the Christian houses that we sent to said, ‘Well, I’m not sure this is Christian enough. It’s a good story, it’s good writing, but we kind of are looking for things a little bit more straightforward, more easily recognizable as Christian,’” Smucker says, “and then the secular houses that we sent out to said, ‘Oh well, this is too religious.’”

Smucker eventually found a publishing home at Revell, which also published Smucker’s latest book, Once We Were Strangers, a nonfiction account of his friendship with a Muslim Syrian refugee.

Reaching a mainstream audience continues to be a challenge for authors who write books that reflect their Christian faith.

“You want to reach as many people as possible with hope,” Doering says, “and so the desire to write something that’s going to be scripturally consistent, but that would reach beyond the borders of someone who is going to church and would reach someone who needs hope…I think that’s a challenge for authors. They would really love to keep the door open and reach those people.”