Second lady Karen Pence recently came under fire for returning to her teaching job at Immanuel Christian School in Springfield, Va. Critics noted that the school has a ferociously anti-LGBTQ policy, banning students and families from “condoning . . . homosexual activity.” Conservatives rushed to her defense. Her husband, Vice President Pence, denounced the attacks on his wife and the school as “deeply offensive.” Journalist David French warned that liberals were espousing a “deep intolerance” of conservative evangelical beliefs. Journalist Ben Shapiro caustically noted that the school was merely enforcing “Christian standards of sin that have not changed in 2,000 years.”

In taking up this line of defense — that the school is merely defending traditional Christian beliefs — conservatives are rushing headlong into a century-old culture-war trap, trying to pick and choose which historic tenets deserve a doughty defense, and which can change with the times. There may be underlying principles here, but they are not those of historical consistency.

Calling the school’s policy on sexuality nothing but “historic, orthodox Christian teaching,” French advanced the argument that the school has adhered to ancient truths while the rest of society crumbled into desperate immorality around it.

The problem is, it hasn’t. When it comes to other elements of the school’s statement of belief, the school embraces recent innovations. For instance, the church’s belief statement insists on a certain form of creationist belief, one in which “God spoke the heavens, the earth and all living things into existence in six days.”

That creation myth may sound as old as the Bible itself, but as an article of faith, it’s practically brand new. Of course, Christians have always believed that God created everything. When He did so and whether He did so in six days, however, have long been bones of contention among conservative evangelical Protestants, as historian Ronald L. Numbers has shown. In the 1920s, for instance, even William Bell Riley, a leader of the staunchly conservative fundamentalist movement, rejected young-Earth notions. As Riley put it in 1927, there was not “an intelligent fundamentalist who claims that the earth was made six thousand years ago; and the Bible never taught any such thing.”

It was only in the 1960s that large numbers of evangelical Protestants began insisting on a literal six-day creation as the true biblical belief, along with other ideas such as a worldwide flood and a very short timeline for all of human and geological history. The catalyst for this transformation: Henry Morris and John Whitcomb Jr.’s forceful 1961 polemic “The Genesis Flood.” In that hugely influential book, Morris and Whitcomb hoped to win evangelicals to one side of the long-running debate about creation and evolution. They hoped to convince conservatives that belief in ideas such as a literal six-day creation was “absolutely essential to the entire edifice of Christian theology, and there can simply be no true Christianity without it.”

This argument was something new. But it caught on because so many conservative evangelicals shared Morris and Whitcomb’s struggle to make sense of new social and scientific realities. By the end of the 1950s, mainstream scientists had figured out many of the mysteries of evolutionary theory. By 1959, as historian Edward Larson recounted, “the modern [evolutionary] synthesis had become virtual dogma within biology.” Conservative evangelical intellectuals faced a stark choice. Some, such as Bernard Ramm, argued that evangelicals could accept modern science without jeopardizing their historic biblical faith.

Morris and Whitcomb, on the other hand, offered a much more radical option: Conservative evangelicals could create a “science” all their own. They could embrace an innovative new approach for Christians by discarding mainstream science entirely. As much as this idea has become common in the seven decades since, it should not obscure the fact that insistence on this specific kind of creationism is an innovation, one that Immanuel Christian School seems to have embraced.

This raises serious questions in the case of Karen Pence. How can conservatives defend one part of a statement of faith as ancient, unchanging orthodoxy, when the same statement includes innovative ideas as well? How can they introduce new ideas into their list of supposedly unchanging beliefs? Most bitingly, how can they take cover behind the idea that they are bound to enforce ancient orthodoxies when in fact they change their own ideas about orthodoxy all the time?

This challenge is as old as orthodoxy itself. In its current American culture-war form, it has confronted religious conservatives for almost a century. In 1925 at the famous Scopes trial, for instance, evangelical defender-of-the-faith William Jennings Bryan took to the witness stand to answer the questions of the skeptic Clarence Darrow. The interchange has rightly gone down in history as one of the most dramatic courtroom conflicts in American history, even if its historic facts have been mutilated by movies such as “Inherit the Wind.”

The confrontation offered Bryan a chance to defend conservative evangelical principles, and it offered Darrow a chance to poke holes in them. However, as Darrow’s co-counsel Arthur Garfield Hays pointed out, the real point was not to ridicule Bryan or conservative religion in general. Rather, Darrow hoped only to get Bryan to admit that even Bryan interpreted the Bible — even a little. If Bryan did, then conservatives “must have agreed that others have the same right.”

And Bryan admitted it. He got laughs from the courtroom crowd when he explained that God may have used figurative language in the Bible in some places, that God “may have used language that could be understood at that time. . . . Instead of using language that could not be understood until Darrow was born.”

In the end, however, Darrow won the point, because not even the most fervently conservative biblical Christian takes the entire Bible literally. Some parts are clearly meant to be poetic, and readers need to decide how to read every section. Bryan had not seen the rhetorical trap until it was too late. Because everyone must necessarily interpret Scripture, conservatives can’t take refuge behind the idea that they are merely implementing God’s policies.

For Pence’s defenders today, this lesson is crucial. They can either defend Immanuel Christian School as merely enforcing millennia-old Christian beliefs or they can defend recent creationist innovations. They can either insist on anti-LGBTQ rules as merely ancient Christian doctrine or they can insist on radical 1960s creationist bombshells. In the end, they must choose between taking moral responsibility for their own anti-LGBTQ beliefs — even though the rest of society sees them as starkly bigoted — or seeking shelter behind the Rock of Ages. They cannot have their orthodoxy and eat it, too.