In the debate over whether Iraq is a "just war," in Christian terms as laid out by Augustine in the fourth century and amplified by Aquinas, Luther and others, Bush has strong support from his base. Leading advocates for the moral virtue of his position include Richard Land, the key leader of the Southern Baptist Convention's political arm and Michael Novak, the conservative Catholic theologian.

But Bush faces a mighty force of religious leaders on the other side, including the pope, and he will meet with a papal envoy this week, Newsweek has learned. "People appreciate his devotion to faith but, in the context of war, there is a fine line, and he is starting to make people nervous," says Steve Waldman, the editor and CEO of Beliefnet, a popular and authoritative Web site on religion and society. "They appreciate his moral clarity and decisiveness. But they wonder if he is ignoring nuances in what sounds like a messianic mission."

The atmosphere inside the White House, insiders say, is suffused with an aura of prayerfulness. There have always been Bible-study groups there; even Clintonites had one. But the groups are everywhere now, Fineman reports.

The language of good and evil -- central to the war on terrorism -- came about naturally, says David Frum, the author and former Bush speechwriter. From the first, he says, the president used the term "evildoers" to describe the terrorists because some commentators were wondering aloud whether the United States in some way deserved the attack visited upon it on September 11, 2001. "He wanted to cut that off right away," says Frum, "and make it clear that he saw absolutely no moral equivalence. So he reached right into the Psalms for that word." He continued to stress the idea, Fineman reports. Osama Bin Laden and his cohorts were "evil."

In an accompanying essay, Martin E. Marty, a former president of the American Catholic Historical Association and a professor emeritus at the University of Chicago, writes about the effects of Bush's rhetoric on world religious leaders. "One hopes that the Bush people will keep in mind that claims of God's always being on our side are alienating to many former or would-be allies. More dangerous is that Bush's God talk will set the tinderbox that is the Muslim world on fire. Neither the president nor the American Christian majority have to yield their own faith in order to get along, but how they express it matters," Marty writes.

He writes that few doubt Bush is sincere in his faith. "The problem isn't with Bush's sincerity, but with his evident conviction that he's doing God's will."

Marty writes that the billion humans in the Muslim world, leaders and followers alike, had good reason to seethe when the evangelist who prayed at Bush's Inaugural -- and who remains close to the president -- persisted in calling Islam "a very evil and wicked religion." "The administration had to reject that claim -- and it did. Regular appearances by the president at meetings of certain evangelical groups, however, make it hard for friendly Muslims not to hear the word 'Islam' whenever Bush portrays 'terrorists' as absolute evils. And, as evangelical theologian Richard Mouw points out, 'Those inflammatory statements stimulate further antagonism on the part of Muslim extremists,' who can go recruiting among moderates," Marty writes.