Since the founding of the republic, most Americans have believed there is an important connection between personal character and political leadership. Many qualities define character. But thanks to male politicians on both sides of the aisle—including Newt Gingrich and Bill Clinton, Arnold Schwarzenegger and Eliot Spitzer, John Ensign and John Edwards—the issue of character often gets reduced to marital fidelity. Which raises the question: How relevant is adultery when it comes to choosing a president?

Betrayal—or no big deal?

On one end of the spectrum are those who believe the issue is open-and-shut. The argument goes like this: a person who betrays his spouse may well betray other commitments, including defending the Constitution. Unfaithfulness unquestionably bears on character, and character in public officials matters. “Betrayal is a garment without seams,” in the words of Professor Robert King. Serial infidelity can be a sign of other maladies, including narcissism and compulsiveness, recklessness and deception. And presidents, like athletes, are role models. The NFL has a personal conduct policy; shouldn’t we expect something similar for our chief executive?

For others, infidelity by a politician is a matter of indifference. Presidents take an oath to uphold the Constitution, not to live by the moral commands of the Bible. And it’s often the case that infidelity has no bearing on a person’s public duties.

On top of that, there are plenty of sins that are condemned in the Hebrew Bible and the New Testament. Why focus on infidelity instead of self-righteousness, bitterness, avarice, or lack of charity? And of course a person who cheats on his spouse might also embody virtues in other arenas (for example, battlefield valor). Some of the most important figures in American history—from Thomas Jefferson to Franklin Roosevelt to Martin Luther King, Jr.—are believed to have cheated on their wives. Should their voices have been silenced because of their indiscretions?

The Churchill-Chamberlain test

Assume that during World War II the choice was between an unfaithful Winston Churchill and a faithful Neville Chamberlain. With the benefit of hindsight, who would most of us prefer as prime minister? (For the record, Churchill was known to be devoted to his beloved Clementine.)

There are, then, strong arguments on both sides of this debate, which is why many of us are on a continuum. Facts and circumstances are crucial. Was an act of infidelity an aberration or part of a pattern? What levels of deception and cover-up were involved? Was there abuse of power or were there unusual displays of cruelty and callousness involved? Does adultery manifest other character defects that are likely to spill over into one’s public actions?

These are tricky matters to sort through. Every saint has a past and every sinner has a future, in the words of Oscar Wilde. And what role should grace and forgiveness play in all this?

Cheap grace

Too often, especially in politics, there is a habit to dispense what one theologian called “cheap grace.” Grace doesn’t mean ethical infractions are forgotten and never taken into account. At the same time, men are not angels. Sin afflicts us all. And most of us believe in, and all of us are in need of, redemption. How to balance grace and accountability is a matter that every one of us deals with in an imperfect and selective manner. Too often, we employ different standards based on our political affiliations and ideological predilections. We take similar facts and interpret them in very different ways, depending on how well they reflect on those whom we support versus those whom we oppose.

In “The Death of Outrage,” William J. Bennett wrote, “The founders (like the ancient Greeks) believed it was important that the head of the good polity be a man of good character, and they advocated that the office of the presidency be filled by persons whose reputation for integrity inspires and merits confidence.”

Mr. Bennett goes on to quote the beautiful words said of George Washington upon his death: “The purity of his private character gave effulgence to his public virtues.”

We can do better

To find someone as virtuous as Washington is rare. But we should be able to do better than someone who, when asked by his then-wife (Marianne Gingrich) how he could give a speech full of high sentiments about compassion and family values while simultaneously committing infidelity, reportedly answered, “It doesn’t matter what I do…. It doesn’t matter what I live.”

Actually, it does.

Peter Wehner is a senior fellow at the Ethics and Public Policy Center. Portions of this piece first appeared on Commentary magazine’s website Contentions.