There is something un-Christian about the Gospel According to Paul Ryan. So, at least, says Ryan’s Catholic Church.

In an interview with the Christian Broadcasting Network’s David Brody this month, Ryan, the author of the House Republican budget endorsed by Mitt Romney, said his program was crafted “using my Catholic faith” as inspiration. But the U.S. Conference of Catholic Bishops was not about to bless that claim.

A week after Ryan’s boast, the bishops sent letters to Congress saying that the Ryan budget, passed by the House, “fails to meet” the moral criteria of the Church, namely its view that any budget should help “the least of these” as the Christian Bible requires: the poor, the hungry, the homeless, the jobless. “A just spending bill cannot rely on disproportionate cuts in essential services to poor and vulnerable persons,” the bishops wrote.

In fact, Ryan would cut spending on the least of these by about $5 trillion over 10 years — from Medicaid, food stamps, welfare and the like — and then turn around and award some $4 trillion in tax cuts to the most of these. To their credit, Catholic leaders were not about to let Ryan claim to be serving God when in fact he was serving mammon.

“Your budget,” a group of Jesuit scholars and other Georgetown University faculty members wrote to Ryan last week, “appears to reflect the values of your favorite philosopher, Ayn Rand, rather than the Gospel of Jesus Christ. Her call to selfishness and her antagonism toward religion are antithetical to the Gospel values of compassion and love.”

Ryan didn’t turn the other cheek. He showed up at Georgetown on Thursday to deliver a previously scheduled lecture, and lecture he did. He said the faculty members would benefit from a “fact-based conversation” on the issue. “I suppose that there are some Catholics who for a long time thought they had a monopoly . . . on the social teaching of our church,” he said, but no more. “The work I do as a Catholic holding office conforms to the social doctrine as best I can make of it.”

From the balcony, a group of young demonstrators answered Ryan by holding up a banner with the message “Stop the War on the Poor: No Social Justice in Ryan’s Budget.” On the plaza outside, more protesters held a banner asking: “Were you there when they crucified the poor?” A man wearing a bedsheet, sash and sandals, with a name tag identifying him as “GOP Je$us,” read a new version of the Beatitudes: “Blessed are the rich: The reign of the world is ours. . . . ”

For the young chairman of the House Budget Committee, it was a timely lesson: However much Ryan may wish it, God does not take sides in politics. Ryan, transparently positioning himself to be Romney’s running mate, may well believe that he is on a mission from God. But in a democracy, such fanaticism makes people such as Ryan unable to make necessary compromises.

The rebuke of Ryan is a credit to the Catholic leaders, because they are displaying their doctrinal consistency even as politicians embrace church teachings selectively. Republicans hailed the Catholic bishops when they were opposing the Obama administration’s policy to expand contraceptive coverage; likewise, they cite the church’s opposition to abortion. But these same lawmakers have little interest in the church’s position against the death penalty or its opposition to the Arizona immigration law.

The bishops, in opposing Ryan’s budget, called for “shared sacrifice by all, including raising adequate revenues.” But Ryan challenged the theologians’ theology. “The holy father himself, Pope Benedict, has charged that governments, communities and individuals running up high debt levels are, quote, ‘living at the expense of future generations,’ ” he said from the pulpit in Georgetown’s ornate Gaston Hall.

Ryan argued that government welfare “dissolves the common good of society, and it dishonors the dignity of the human person.” He would restore human dignity by removing anti-poverty programs. The moderator asked the chairman about “the moral dimension” of a budget that gives tax cuts to the wealthy and cuts spending for the poor. Ryan’s answer included the phrase “subchapter S corporations.”

Spending on programs such as food stamps and college Pell Grants is “unsustainable,” he said. If government does too much for the poor, “you make it harder” for churches and charities to do that work.

It was a bold economic — and theological — proposition. Even Jesus said to render unto Caesar that which is Caesar’s. Ryan would rather give the rich a tax cut.

danamilbank@washpost.com