Rick Santorum is a man who seems to hold sincerely held religious beliefs. The problem is that he thinks everybody that matters holds (or should hold) the same beliefs that he does, or at least should be forced to live in a country that operates by the principles that follow from those beliefs.
Santorum has accused Obama of operating from a "phony theology" (one not based on the Bible). That suggests that Santorum thinks a president is supposed to impose a biblical theology on all presidential work--and that Santorum intends to impose his own "correct" theology if he were to be elected president. See Santorum Questions Education System and Criticizes Obama, New York Times (Feb. 18, 2012). That approach fits with Santorum's idiosyncratic views on how religion is supposed to influence public life: Santorum has made a point of claiming that he does not hold with the founding principle of separation of church and state--a principle enunciated by Thomas Jefferson, ascribed to by Abraham Lincoln, and articulated splendidly by John F. Kennedy. See Joan Walsh, Santorum's JFK Story Makes Me Want to Throw Up, Salon.com (Feb. 26, 2012).
This issue is worth pointing out clearly. Here's what Santorum said
I don’t believe in an America where the separation of church and state is absolute. The idea that the church can have no influence or no involvement in the operation of the state is absolutely antithetical to the objectives and vision of our country. (emphasis added)
And here's what the statesman Kennedy said when confronting the concerns of the Southern Baptist Convention that a Catholic in office would implement the laws under the dictate of the Pontiff in Rome rather than the U.S. Constitution.
I believe in an America that is officially neither Catholic, Protestant nor Jewish; where no public official either requests or accepts instructions on public policy from the Pope, the National Council of Churches or any other ecclesiastical source; where no religious body seeks to impose its will directly or indirectly upon the general populace or the public acts of its officials; and where religious liberty is so indivisible that an act against one church is treated as an act against all.
What does Santorum's theology look like and how will it influence public policy under a Santorum presidency? Santorum apparently thinks public schools are a bad idea (he's likened them to "factories") and that all children should be able to be home schooled (and indoctrinated in a parent's religious preferences) at taxpayer cost. See Santorum Questions Education System and Criticizes Obama, New York Times (Feb. 18, 2012); Santorum Exposed: why is Santorum spending your tax dollars on his family (noting that Santorum took $100,000 from Pennsylvania for an online program for his home-schooled kids, even though he resided in Virginia at the time). He thinks kids get "weird socialization" in public schools. Rick Santorum, Kids Get Weird Socialization in Schools, Huffington Post (Feb. 22, 2012). We already have weakened public schools by permitting taxpayer funds to pay for "nonreligious" items at religious private schools, such as text books and transportation. Since money is fungible, that payment merely subsidizes more religious expenditure on religious education and deprives children in public schools of much needed resources to deal with the huge lingering infrastructure problems of our public school systems. We don't need to go even further in that direction by moving religion into public schools wholesale, or moving even more children into ideological indoctrination through taxpayer-funded schooling.
Santorum's theology is backward on women as well, seeming to think more women should be anchored in the kitchen with numerous progeny pulling on apron strings that signify the most satisfying role for women (in his book). One worries how that would play out in a Santorum presidency that could cut off funding for disfavored activities through executive orders, and his public statements bode ill for how it would pan out. Santorum apparently thinks the feminist revolution is bad, because it has made it harder for women to choose to stay at home. See Santorum faces questions on women in the work force, New York Times (Feb. 12, 2012). In contradistinction to the importance of individuals' rights under the First Amendment, he seems to think that every religious institution should be able to impose its beliefs on its workers (no matter what their beliefs are): under Santorum, a woman working in any capacity for the Catholic Church could not be covered in her health care plan provided by her employer for contraception. See Social Issues Rule Day in Candidates Race, AP (Febl 12, 2012) (noting Santorum's comment that the contraception rule forces churches to do something against their basic (institutional) tenets). He thinks voters should be aware of his religious faith and should consider that in determining whether to vote for him. And his religious faith doesn't believe in birth control, so he wants to be sure that the tax code provides a huge tax exemption for each child in multi-child families--but not a refundable tax credit that would be of real use to a poor working mother with one child to care for. See Santorum letter, Raise the exemption for children, not the child tax credit, Wall St. J (Feb. 25, 2012) (claiming that he wants an $11,100 personal exemption per child for working families but is against a child tax credit that would be refundable, so is "innocent" of "expanding welfare").
Santorum's theology doesn't seem to find it problematic when a government system systematically redistributes resources upwards to the benefit of the wealthy. His tax plan would result in zero taxation on unearned income, the primary type of income of the wealthy. Welfare for the rich is apparently fine and dandy under Rick Santorum's version of morality.