Eric Gay / AP Republican presidential candidate Rick Santorum during a Ohio Christian Alliance luncheon on Feb. 18, 2012

We have been here before. In 1908, the Unitarian William Howard Taft ran against the evangelical William Jennings Bryan. Bryan supporters attacked Taft’s faith; that year a Pentecostal newspaper wrote: “Think of the United States with a President who does not believe that Jesus Christ was the Son of God, but looks upon our immaculate Savior as a … low, cunning imposter!”

Rick Santorum seemed to be working in the Bryan tradition on Feb. 18 when the GOP presidential candidate said that President Obama adheres to “some phony theology. Not a theology based on the Bible. A different theology.”

Asked about the comments on CBS’s Face the Nation, Santorum dissented from the more extreme interpretation of his remarks — only to go on to raise more questions than he answered. In doing so, Santorum may please parts of the deeply conservative base of his party but at a high price: that of politicizing religion in a decidedly un-American way. By raising Obama’s “theology,” Santorum risks reviving implicit religious tests for office.

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“I accept the fact that the President’s a Christian,” Santorum said. “I just said that when you have a worldview that elevates the earth above man and says that, you know, we can’t take those resources because we’re going to harm the earth by things that frankly are just not scientifically proven, like for example that politicization of the whole global-warming debate, this is just all an attempt to theocentralize power, to give more power to the government.”

So far, so good: the rhetoric is overheated, yes, but fairly routine. Then Santorum added: “I’m talking about the belief that man should be in charge of the earth and should have dominion over it and should be good stewards of it.”

Here Santorum heads into treacherous territory. The allusion to “dominion” evokes Genesis 1:28, in which the Lord blessed Adam and Eve and told them, “Be fruitful, and multiply, and replenish the earth, and subdue it: and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth.”

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This is the language of what’s known as “dominionist theology,” the worldview that Christians have a divine mandate to control or at the very least influence earthly government and culture. Rick Perry’s rise cast light on the dominionists’ theology and ambitions last year; Santorum’s now the last man standing who could serve as a plausible vehicle for culturally and politically conservative Christians uncomfortable with both Obama and Mitt Romney.

Religious faith is as legitimate a subject of political inquiry as any other question of philosophy or experience, for theological beliefs and their applications to real-world situations can affect what a President thinks and how he acts.

In my view, then, Santorum was not out of line in raising the question. But he has to be ready now to put himself in the dock as well.

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