This article was originally posted at Huffington Post.

The Donald Trump “sex tape” that has sent Republicans scurrying like rats from a sinking barge—just weeks before the presidential election—is spectacle enough. Now add to this cavalcade of confusion the volte-face of a handful of prominent evangelical voices who, up until this moment, declared Trump “a morally good choice.” Such reversals do not signal remorse and enlightenment, however, but rather desperation and denial.

Everyone who has endorsed Trump, politician or preacher, has been diminished by the association. Yet chief among these tragic figures is Wayne Grudem, professor of theology and biblical studies at Phoenix University and author of Systematic Theology: An Introduction to Biblical Doctrine, a required text in many evangelical colleges and seminaries. In late July, Grudem published a 5,000-word defense of Trump that kicked up a firestorm. No other evangelical thinker attempted such an ambitious project—the reconstruction of Donald Trump into a credible presidential candidate—couched in the language of moral theology and prudential politics.

In reality, Grudem’s polemic was shot through with half-truths, facile assumptions, tortured logic, and emotional manipulation. His eleventh-hour abandonment of Trump suggests something of the anguished state of militant evangelicalism.

Offering not a scintilla of evidence, Grudem at first concluded that “Trump’s character is far better than what is portrayed by much current political mudslinging, and far better than his opponent’s character.” Declaring the need to make “an ethical decision” in this election, Grudem wrote, “we should base the decision on the most likely results. In this case, the most likely result is that Trump will do most or all of what he has said.” Put aside the inconvenient fact that Trump’s political views are amorphous and malleable, that he shows no capacity to work with the legislative branch of government, and that much of his agenda represents an assault on the constitution and the international norms upholding human rights.

Grudem ended his essay with a moral taunt about as damning as any Puritan jeremiad ever delivered:

But the most likely result of not voting for Trump is that you will be abandoning thousands of unborn babies who will be put to death under Hillary Clinton’s Supreme Court, thousands of Christians who will be excluded from their lifelong occupations… thousands of sick and elderly who will never get adequate medical treatment when the government is the nation’s only healthcare provider, thousands of people who will be killed by an unchecked ISIS, and millions of Jews in Israel who will find themselves alone and surrounded by hostile enemies. And you will be contributing to a permanent loss of the American system of government due to a final victory of unaccountable judicial tyranny.

Yes, gentle Christian voter, this apocalyptic cascade of events—the abandonment of entire classes of people to perdition and the permanent loss of American democracy—must be placed on your shoulders for failing to endorse Donald Trump for president. This is what passes as serious ethical reflection in evangelical circles.

But of course that was Wayne Grudem’s position in late July. The Trump video, in which the candidate boats of sexually assaulting women, apparently transformed Grudem’s political theology overnight. His pious defense of the Republican nominee morphed into a slippery, Trump-like non-apology for having done so. “I previously called Donald Trump a ‘good candidate with flaws’ and a ‘flawed candidate,’” he wrote in Townhall.com, “but I now regret that I did not more strongly condemn his moral character.”

The deepest problem for Grudem, and others like him, is that his original manipulation of Trump’s record was a deliberate evasion of the truth. Even now, Grudem cannot speak frankly, in total candor, about his previous endorsement. “I did not take the time to investigate earlier allegations in detail, and I now wish I had done so,” he says. “If I had read or heard some of these materials earlier, I would not have written as positively as I did about Donald Trump.”

The evasion of truth persists: Grudem expended 5,000 words to reimagine Donald Trump according to his liking, but “did not take the time to investigate” Trump’s public record and character? Like everyone else following Trump’s ascendancy, he knew all about the lies and misstatements, the infidelities, the misogyny, the mockery of the disabled, the race-baiting rhetoric, the attacks on a grieving gold-star family, and on and on. Grudem did not merely write “positively” about Trump; he wrote dogmatically, with moral certitude. “I feel the force of the words of James,” he intoned. “Whoever knows the right thing to do and fails to do it, for him it is sin.” And for all this sanctimony he offers no apology—not to his students, for whose moral formation he is partially responsible, nor to the larger Christian community he hoped to influence.

In the war of words during this disgraceful campaign, on both sides of the political aisle, truth has been the most conspicuous casualty. But how do we explain the failure to uphold basic norms about truth-telling among Bible-believing Christians?

History offers some clues. There is a belligerent strain in Protestant Christianity, embodied in the Calvinist tradition to which Grudem belongs, which has been willing to sacrifice moral and biblical truth in the pursuit of noble ends. John Calvin, supremely confident he had recovered a neglected view of predestination, sought to build a community of “the elect” in Geneva—and adopted a theology justifying the banishment, vilification, and execution of dissenters in order to achieve it. His doctrine was a violent rejection of the life and teachings of Christ. The English Puritans, overwhelmingly Calvinist, viewed the kingship of Charles I as the great obstacle to their hopes for a godly commonwealth. They wanted to blow up the old order. They instigated a civil war, orchestrated the king’s execution, and turned to a “man on horseback” to inaugurate a new regime: Oliver Cromwell. Like the Puritan project in Salem, Massachusetts, the experiment did not end well.

It is perhaps no accident that Grudem is considered a leading light among the “new Calvinists,” a small but vocal group of hard-line thinkers and preachers who hold an uncompromising view of the Calvinist doctrines of election and predestination. Like the old Calvinism, the new Calvinism teaches its adherents that they are a righteous remnant battling a godless and hostile political culture. This is not the place to debate Protestant theology, but the tribalism and dogmatism of historic Calvinism may have found a political outlet. As one theologian and critic put it recently: “I think Calvinism is the Donald Trump of theology.”

That’s a harsh verdict. Many believers outside the Calvinist or Reformed tradition, after all, have endorsed Trump, and some prominent Calvinists have denounced him as unfit for the presidency. Nevertheless, the rise of Trump represents an illness in the body politic—a politics of self-righteous rage that has an analog in militant Christianity. It is time, inside the church, for a ruthless moral inventory. As the Scripture warns: “Judgment begins in the house of God.”

Joseph Loconte is an associate professor of history at the King’s College in New York City and the author of A Hobbit, a Wardrobe, and a Great War: How J.R.R. Tolkien and C.S. Lewis Rediscovered Faith, Friendship, and Heroism in the Cataclysm of 1914-1918.