GOP presidential candidate Donald Trump pauses during a meeting with members of the National Border Patrol Council at Trump Tower in New York on Oct. 7. (Evan Vucci/AP)

This opinion piece is by R. Albert Mohler Jr., president of the Southern Baptist Theological Seminary in Louisville.

America’s evangelical Christians, awakened by the millions to political activism barely a generation ago, now find themselves in what can only be described as a crisis of conscience. The immediate and excruciating crisis has a name — Donald Trump.

This past weekend, political analysts described the situation inside the Trump campaign as “DEFCON 5,” an acknowledgment that the revelations of a sexually explicit taped conversation with Trump posed the prospect of immediate defections from key Trump constituencies, and evangelicals are at the top of that list.

Why now? The Donald Trump revealed on the 11-year old tape did not reveal anything that evangelicals should not have already known about the Republican nominee. Plenty of venality was in abundant evidence, even in the candidate’s own books.

How could “family values voters” support a man who had, among other things, stated openly that no man’s wife was safe with him in the room? A casino titan who posed for the cover of Playboy magazine? A man who boasted that he did not repent of his (well-documented) sins and would not?

That answer also has a name — Hillary Clinton. The evangelical political awakening came at the end of the 1970s, when conservative Christians became more aware of a looming cultural crisis and newly aware of the possibility of responding to that crisis with political activism.

A marriage of convenience between evangelical Christians and the Republican Party resulted when the divide over issues like abortion and the definition of the family — both central to the sexual revolution — became institutionalized in the trajectories of the two major political parties.

The Democrats became the party of abortion rights and cheerleading for a moral revolution that would eventually include same-sex marriage. Republicans defended the sanctity of human life and the normativity of the natural two-parent family headed by a father and a mother. An entire platform of policies and positions drove a wedge between the two parties and evangelicals became a vital constituency of voters for the Republican Party.

The days of sitting on the political sidelines were over. Evangelicals learned to see presidential elections in light of nominations to the Supreme Court and other manifestations of presidential power.

There was more to this marriage of convenience, of course, but a political instinct became second nature to American evangelicals. They marched by the millions into precincts and voting booths and voted for the Republican presidential candidate.

That political instinct is what leads to the current crisis. This year, the Republican nominee is, in terms of character, the personification of what evangelicals have preached (and voted) against. Married three times, flaunting Christian sexual mores, building his fortune and his persona on the Playboy lifestyle, under any normal circumstances Trump would be the realization of evangelical nightmares, not the carrier of evangelical hopes.

But when Trump claimed the Republican nomination, evangelicals faced a new and very awkward situation. Some evangelical leaders adopted a “never Trump” position early in the primaries. I am among those who see evangelical support for Trump as a horrifying embarrassment — a price for possible political gain that is simply unthinkable and too high to pay.

Nevertheless, I know very well many of the evangelical leaders who found a way to support Trump, and many are close friends. The leaders I have in mind are principled men and women of Christian character and conviction.

They are not wrong to see the future of the Supreme Court in the balance and to see Hillary Clinton as a threat to values and causes we see as vital to human flourishing. They are not wrong to see a restoration of the Clinton dynasty as a grave danger to unborn life and to values we believe to be essential to America’s cultural health and influence in the world. They are not wrong to see Hillary Clinton’s public positions and personal character as disqualifying. They are not wrong to understand that elections have consequences and that the election of Hillary Clinton would be a radical advance for liberal causes that will have lasting, perhaps irreversible consequences.

They are wrong, I believe, to serve as apologists for Donald Trump.

The release of the sexually explicit tape revealed Trump in a light that must be the worst nightmare for the candidate’s campaign. It revealed a sexual predator, not merely a playboy.

Evangelicals committed to the gospel of Jesus Christ know that each one of us is a sinner desperately in need of salvation and the forgiveness of sins. We believe in the power of Jesus Christ to save and in salvation that comes by grace alone to those who believe in Christ and repent of their sins. Evangelicals sing “Amazing Grace” with gusto because we have experienced it and want to share the good news of the gospel with everyone.

We tell our story as testimony, and evangelicals were drawn to candidates who shared that testimony.

They supported a divorced actor who, as governor of California, signed into law liberal measures on no-fault divorce and abortion. They supported a Republican nominee who admitted a problem with alcohol earlier in life. Both of these candidates identified themselves with evangelicals and told their own stories of redemption.

In retrospect, evangelicals invested far too much hope in elections and presidential candidates, but from 1980 onward they supported Republican candidates who had for many years seen the light and lived their lives free from scandal.

Then came The Donald. Sadly, many evangelicals overlooked his racial signaling and his crude nationalism. Rightly frustrated with the political status quo and the dominance of elites, they were attracted to Trump’s populism. Some became apologists for Trump and encouraged evangelical voters to overlook the candidate’s past and, as the argument is often put, to remember that the election is about voting for a president, not for a Sunday school teacher.

That argument is what collapsed beyond all credibility with the release of the tape. Donald Trump is not just disqualified from being a Sunday school teacher. Honest evangelicals would not want him as a next-door neighbor.

Trump’s horrifying statements, heard in his own proud voice, revealed an objectification of women and a sexual predation that must make continued support for Trump impossible for any evangelical leader.

Perhaps Trump will offer his own account of a sudden conversion and contrition in coming days. The problem with that hope is that Trump has continuously undermined the plausibility of such a testimony. Even now his empire is built on venality, and he has continued to project his Olympian persona as the contradiction of Christian morality.

His apologists are right: The stakes could not be higher. Jesus famously asked, “What will it profit a man if he gains the whole world and forfeits his soul? Or what shall a man give in return for his soul?” (Matthew 16:26)

Those are the questions now faced by America’s evangelicals. Like all voters, American Christians will enter the voting booth and, we hope, vote as led by their consciences. But leaders are held to a much higher standard, and continued public arguments that offer cover for Donald Trump are now not only implausible but excruciating.

The marriage of convenience is over, at least for now. Perhaps the best we can hope for in this sad election cycle with these two unsupportable candidates is that we do not allow a national disgrace to become the Great Evangelical Embarrassment.

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