By MICHAEL GERSON

     WASHINGTON — Donald Trump’s offenses against taste, tolerance and truthfulness are coming so fast that it is hard to pick out individual cases. But let’s linger on his recent foray into Christian theology.

     During a speech in Fort Dodge, Iowa, Trump pronounced Ben Carson’s story of conversion from violent troublemaker to Christian to be so much “crap.” “He goes into the bathroom for a couple of hours, and he comes out, and now he’s religious? Give me a break. It doesn’t happen that way,” said Trump.

     In Christian history, it has often happened that way. Around 35 A.D., a nasty character named Saul got knocked from (and to) his ass on the road to Damascus and became the utterly transformed Paul. In 386 A.D., Augustine heard a child’s voice chanting, “Take up and read,” opened a Bible randomly to Paul’s letter to the Romans, was convicted to the core, and abandoned the life of a hard-partying pagan. Around 1510, a monk named Martin Luther understood Paul’s letter in a new way — one version locates this revelation in the “cloaca,” or bathroom — and “felt I was altogether born again and had entered paradise itself through open gates.” On May 24, 1738, John Wesley heard someone reading Luther’s Preface to the Epistle of Romans in a meeting at Aldersgate, and at 8:45 p.m. felt his “heart strangely warmed.”

     All of these cases weigh against Trump’s theological claim — which also makes little political sense in the state of Iowa, where the Republican Party is heavy with evangelical Christians, for whom conversion is a common experience.

     But this is not really a political matter at all, demonstrated by another conversion. Bob Beckel was, famously, Walter Mondale’s campaign manager in a 49-state loss. He was a trusted fixer at the State Department and White House, then a progressive TV commentator. Through most of this he was also an alcoholic, a drug abuser and a womanizer who kept hitting rock bottom only to find new bottoms beneath.

     We know this from Beckel’s transparent and compulsively readable autobiography , “I Should Be Dead: My Life Surviving Politics, TV and Addiction.” He gained his survival skills from dealing with an alcoholic and abusive father. “I learned how to wear a mask at all times and reveal my true feelings to no one.” Later on, this led to a bifurcated life: Mornings at the White House, evenings in dive bars and brothels. A ferocious political ambition, and a tendency toward self-destruction.

     Professionally, Beckel managed an impressive feat: becoming the political dirty trickster for a president, Jimmy Carter, who abhorred dirty tricks. In pursuit of passage of the Panama Canal Treaty, Beckel ran a rogue operation involving opposition research, tilted polling, visits to “Mama’s Health Spa” and political blackmail. Seldom has a boring, respectable objective had a seedier backstory.

     Beckel was also in and out of Alcoholics Anonymous for years, trying to recover without buying into the “Higher Power” portion of the 12 steps. When George W. Bush prevailed in the election crisis of 2000, Beckel, by his own account, began losing contact with reality. On the eve of the inauguration, he found himself in a bar, with a woman, then with her jealous husband pointing a .45 at Beckel’s face. The gun misfired. The next day he watched the inaugural parade from a room at the George Washington University Hospital psychiatric ward.

     The whole story is really worth reading. But through the intervention of friends (particularly columnist Cal Thomas, to whom the book is dedicated) and after some brutally honest self-examination, something decisively changed.

     After resisting a potentially lethal drink, Beckel sat weeping on a rock in the middle of a field. “And I knew,” he writes, “there was a force that had wanted me not to do that, a force that loved me enough to stop me in my tracks and redirect my steps. That loved me? Me? If there is one moment I can point to, a moment when the idea of God’s grace shifted from being some kind of abstract concept to being something flesh and blood, something meaty and rich, something real, that was it.”

     Conversion, in the Christian tradition, requires the recognition of sin and failure, which is the only way the offer of grace makes sense. This, to be honest, is a difficult concept for many of us to accept. But voices as diverse as Carson and Beckel promise something encouraging: that any moment, early or late, can mark the beginning of hope.

     Michael Gerson’s email address is michaelgerson@washpost.com.

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