I was hoping that the archives in Europe would not have wireless. The idea was to have my thoughts stay put in the mid-twentieth century, where they’re supposed to be this month, and not wander to, say, Politico’s website. Alas, the World Council of Churches (WCC) Library here in Geneva has all the twenty-first century amenities. But let me say this about impulsive toggling between finding aides and news sites: every once in a while, it offers a vivid reminder of how useful it can be to tell (or retell) old stories to help make sense of new ones.

Last week, President Obama gave a briefing on developments in Iran that left the press at once impressed with his command of policy detail and confused as to whether he had announced a new diplomatic initiative. This was not the first time his bon mots had prompted head-scratching among those following events in Iran. As protesters took to the streets of Tehran in the wake of the 2009 elections, the White House issued a statement expressing cautious support for the incipient Green Movement with these words: “Martin Luther King once said—‘the arc of the moral universe is long, but it bends toward justice.’ I believe that. The international community believes that. And right now, we are bearing witness to the Iranian peoples’ belief in that truth, and we will continue to bear witness.”

To “bear witness”: Obama’s phrase was widely quoted but not seriously analyzed. Some attacked (and some still attack) the President for leaving the protesters in the lurch; to these commentators, “witness” meant passive spectatorship when a robust intervention was needed. Others found the Administration’s aloofness a shrewd tactic that gave the good guys breathing room while respecting Iranian sovereignty. Few, as far as I know, took note of the Christian roots of the phrase. That’s too bad, because they help to shed light on Obama as a politician, a diplomat with “realist” predilections, and a national phenomenon—and how he manages to be all three at once.

But, who says Obama’s use of this phrase has “Christian roots?” In a basic sense, the idea of bearing witness has nothing to do with religion at all. A witness to a crime, appearing before a court, has no necessary connection with the Absolute. Being in Geneva is actually a good reminder of how widespread this juridical metaphor is among humanitarians at work in the world’s troubled regions: around the corner from my hostel is the Office of the United Nations High Commissioner for Human Rights, which awards a special appellation—“human rights defender”—for anyone who lobbies governments on behalf of human rights, or “bear[s] witness, either in a public forum [. . .] or before a court or tribunal, to human rights violations that have already occurred.”

In my opinion, however, this is not the sense in which Obama uses the phrase. He states that “we” are witness not to injustice but to justice. Specifically, we are witness to a promise that justice will prevail in the end, in spite of the set-backs it faces today. With this meaning we are squarely, I believe, in the Christian tradition.

In the Gospel, Christ is called “the faithful and true witness” (Rev. 13:4) to God’s grace. His followers, in turn, are asked to bear witness to Christ—i.e., to spread the Good News of salvation through Him. Witness here is a reminder that, though our world is shot through with oppression and suffering, there is still reason for hope. God’s love may not always (or ever!) be empirically evident, so the job of witnesses is to testify to what they know “in their hearts.” Their task is to acknowledge the great distance between the earthly and heavenly worlds, while, at the same time, expressing faith in their ultimate reconciliation, scripted to come with the return of Christ. Witness, in other words, manifests hope—is it surprising that the phrase would appeal to Obama?

But Obama’s version of hope is complex. His trademark is a particularly effective balancing of two visions of history—on the one hand, a progressive faith in this world, and on the other a sense for the irrevocable fallenness of man that has, traditionally, been associated with more “eschatological,” otherworldly (and traditionally conservative) strains of Christian faith. It is more or less the balance that Reinhold Niebuhr, whom Obama has cited frequently as an influence, struck at the beginning of the Cold War. But while Niebuhr cast himself as an outsider, a prophet, and a polemicist, Obama wants to be a uniter, rallying both progressives and conservative moderates like David Brooks to his side. Whether this is a bridge that can endure—even beyond one Presidential term—is yet to be seen.

What is clear, after a week of looking through the WCC records, are the perils of a politics that relies too heavily on the idea of “witness.” Witnesses are almost always attacked from both sides—not for nothing were they called martys in Greek (the source, of course, of Christian “martyrdom”). This is what happened to the leaders of the (mostly Protestant) ecumenical movement centered around the WCC in the early 1950s. In 1950, the Council drew crippling criticism when it released a statement expressing its responsibility to bear “concrete witness” to Christ in the face of the unjustified aggression by North Korea against South Korea (the U.N. Security Council had recently condemned the North Korean attack as a “breach of the peace”). Churches in the U.S. and Britain found the document a cowardly prevarication that, in lieu of saying anything, simply reiterated the facts of the situation. Meanwhile, churches from Eastern Bloc countries (and even some in Western Europe) assailed the document as ungodly meddling in worldly affairs. The episode revealed that there would be no easy road ahead for a fellowship that both believers and non-believers had hailed only a few years before as the harbinger of a new age of Christian influence in international affairs. Even for believers, reared on the meaningfulness of Christian witness, bearing it can seem too much—or too little—for this world.