WASHINGTON — In a 2006 speech here, then-Sen. Barack Obama said Jesus' Sermon on the Mount was so "radical" the Defense Department wouldn't survive its application. Earlier this month, the new president suggested the economy couldn't get along without it.

In the middle of a nuts-and-bolts speech at Georgetown University on economic policy, Obama overtly cited the sermon's parable of two men, one of whom builds his house on rock, the other on sand.  "We cannot rebuild this economy on the same pile of sand," the president said. "We must build our house upon a rock."

The reference to Jesus' most famous — and notoriously challenging — sermon quickly drew attention from the media, some of whom labeled the speech "Obama's Economic Sermon on the Mount."

Obama has referred to Jesus' mountainside sermon several times in recent years, sometimes using the same two-houses parable to make a point about sound government policy, at other times using the sermon's wider message of tolerance and love to defend his progressive interpretation of Christianity.

For instance, on the campaign trail last March, and in his book "The Audacity of Hope," Obama has cited the sermon to explain his support for same-sex civil unions.

"If people find that controversial, then I would just refer them to the Sermon on the Mount, which I think is, in my mind, for my faith, more central than an obscure passage in Romans," Obama said at a campaign event in Ohio when a local pastor asked him how he plans to win evangelical votes when he disagrees with many of them about same-sex unions.

In his letter to the Romans, St. Paul condemns homosexual acts as unnatural and "unseemly."

With its turn-the-other-cheek vibe, and "blessed are the peacemakers" Beatitudes, the Sermon on the Mount has long been a favorite of progressive Christians, said Timothy Larsen, a professor of Christian thought at Wheaton College, an evangelical school in Illinois.

"It's deeply important to pacifists," such as Anabaptists, said Larsen, who also co-edited the book The Sermon on the Mount Through the Centuries. "It doesn't fit obviously with civil religion. There's lots of uncompromising stuff in there about not retaliating against enemies."

Those are likely the passages Obama was referring to when he said in 2006 that the Sermon on the Mount is "so radical that it's doubtful that our own Defense Department would survive its application."

Obama was making a larger point during that speech about the folly of using Scripture as an exclusive guide for public policy. But it's equally foolish, he said, for progressives to "scrub language of all religious content."

"If we truly hope to speak to people where they're at—to communicate our hopes and values in a way that's relevant to their own — then as progressives, we cannot abandon the field of religious discourse."

That's why Obama was smart to insert a bit of the Bible in an otherwise dry policy speech on the economy earlier this month, said Jacques Berlinerblau, an associate professor at Georgetown University and author of Thumpin' It: The Use and Abuse of the Bible in Today's Presidential Politics.

Not only was Obama's Sermon on the Mount reference a nod to Georgetown's Jesuit roots, it also "grounded him in the Christian moral tradition and gave the patina of a Christian-based moral argument to his economic policy," Berlinerblau said.

Still, conservative Christians have disparaged Obama's Sermon on the Mount references, accusing him of distorting Jesus' message to sustain his own liberal views. One video that says Obama "mocked and ridiculed" the sermon in his 2006 speech has been viewed more than 4 million times on YouTube.com. Last year, Focus on the Family founder James Dobson reproached Obama for "dragging biblical understanding through the gutter."

But even if conservatives disagree with Obama's scriptural interpretations, they should be glad their president is reading—and talking about—the Bible, said Russell D. Moore, dean of the school of theology of Southern Baptist Theological Seminary in Louisville, Ky.

"Over the last 30 years or so many who hold to President Obama's worldview have criticized evangelicals and Roman Catholics for basing public policy positions on faith principles as a supposed violation of separation of church and state," Moore said.

"If President Obama is acknowledging that he has a religiously informed point of view that could be a positive development," Moore said.

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