It seems the only time the Family Research Council features anything worth reading -- that is seriously contemplating as opposed to criticizing as extremist crankery -- is when they feature Straussian scholars. For the other side arguing contra Kraynak, see this article by Thomas West.
Robert Kraynak, a doctrinaire conservative Catholic and professor of political science at Colgate University, summarizes for the FRC the thesis of his book Christian Faith and Modern Democracy. The whole article (and book) are worth reading. I'll highlight some key points. [Note, I more or less sympathize with his point on the disconnect between Christian principles and founding-era republican principles; however, as my readers can guess, I don't sympathize with his ideal ruling political system.]
First, as Kraynak points out, the notion of "rights" -- unalienable, natural, political, or human -- are not authentically Christian or Biblical concepts:
Problems with Rights
Let us turn first to theories of "rights" and ask if they are compatible with Christianity. As a preliminary observation, I would note that most of the Christian theologians of the past did not develop theories of rights. The greatest of them--St. Augustine, St. Thomas Aquinas, Martin Luther, John Calvin, Richard Hooker, and the American Puritans--had strong notions of justice, derived from natural law and divine law, which enabled them to oppose tyranny, oppression, and exploitation. But their notions of justice and higher law were not the same things as theories of rights. Nor am I convinced by the scholarly work of Brian Tierney that "natural rights" can be found in twelfth-century canon law doctrines of "subjective right." Why not?
The answer, I believe, is that rights are basically claims against authority, either for protections for personal freedom from the arbitrary power of the state or for entitlements from the state for social welfare benefits. Neither of these senses of rights--protections or entitlements--is easily squared with Christian doctrine. Let me offer five reasons why.
In the first place, Christianity puts duties to God and neighbor before claims of rights; and it cannot easily accept the proposition that a right to pursue happiness as one sees fit takes precedence over duties to God and man. After all, the Bible uses the language of divine law rather than the language of rights to express morality and justice; it gives us the Ten Commandments rather than the Bill of (Ten) Rights, and the commands not to kill and not to steal do not necessarily mean that others have a right to self-preservation or to own property. Even the command to love one's neighbor as one's self is not necessarily the same as respecting the rights of others--if, for example, loving one's neighbors means imposing on them for their own good in order to save their souls or to steer them away from sin (as we would wish for ourselves). In other words, divine law commands duties to others and reciprocal obligations, and those commands do not necessarily entail respecting others' rights and may even require subordinating rights to higher duties.
In the second place, Christianity's foundation on divine revelation implies a duty to accept transcendent truth, and Catholicism and Eastern Orthodoxy require acceptance of authoritative pronouncements about truth by the hierarchical Church. This is crucial for Catholics and Orthodox churches, but even Protestants who allow individuals to interpret Scripture for themselves have developed means for promoting orthodoxy and suppressing heresy. It is not easy for any devout Christian to accept a blanket right of individual conscience, especially if it leads to a society indifferent to God or to a society in which cults proliferate and the true faith is marginalized. While defending orthodoxy does not automatically imply theocracy or a confessional Christian state, it is not easy to square with religious liberty either.
Third, the Christian notion of original sin implies distrust of weak and fallible human beings to use their rights properly. Belief in original sin instills in Christians a keen sense of how freedom can go awry and implies that any notion of political freedom must be a conditional good rather than an absolute good. Original sin means weak and corruptible human beings need curbs on freedom by social and political institutions, including the legislation of morality by the state. Of course, many Christian theologians maintain that the corruption of man by original sin does not obliterate his rational nature, but this implies even greater responsibilities for the state--not only to suppress vice and sin, but also to perfect the rational souls of citizens by inculcating moral and intellectual virtues. Such political responsibilities are hard to reconcile with protections for individual rights.
Kraynak then highlights a point I've often noted: The Bible never speaks of political liberty, but whenever it uses terms liberty/freedom, it speaks of spiritual liberty, or freedom from sin:
They also provide insight into why traditional Christianity places more emphasis on "inner freedom"--the freedom of the soul from sinful desires--rather than "external freedom"--the freedom from external political controls, including the controls of a repressive state or the institution of slavery. Thus, when St. Paul spoke of Christian freedom, he meant inner freedom, not the external freedom from the state protected by natural rights. Thus, Paul could say (without contradicting himself) "for freedom Christ has set us free ... do not submit to the yoke of slavery" (Gal. 5:1) and "slaves, obey ... your earthly masters" (Col. 3:22). Paul is not endorsing slavery in his admonitions to obedience; but he is saying something that is hard for modern Christians to understand: Inner freedom from sin is more important than external freedom from oppression, making spiritual freedom a higher priority than claiming one's rights.
Importantly, Kraynak articulates why the Enlightenment philosophy, particularly that of the "state of nature," central to American Founding republican thought, is not Biblical:
Furthermore, Christians (especially Catholics) cannot accept the premise of the natural freedom of the autonomous self that underlies most doctrines of rights. The most influential doctrines of rights emerged from the philosophers of Enlightenment Liberalism (Hobbes, Locke, Rousseau, Kant, Mill, Dewey, and Rawls). They argue that human beings are "born free," and they posit the existence of a state of nature or an "original position" that proclaims human autonomy at the expense of human dependence on God or on fellow human beings and denies natural sociality as well as naturally given or divinely ordained hierarchies. Natural freedom is antithetical to the notion of divinely ordained religious hierarchy in the Church or a natural hierarchy in the family or claims that those who are more wise and virtuous have some legitimate title to rule over those who are less wise and virtuous. Since these notions are inherent in Christian teachings, a Christian doctrine of natural or human rights cannot begin from the assumption of an autonomous self in a state of nature or an original position. The rights must be derived from duties, hierarchies, and prior human goods--a fact that raises the question if they are still rights at all, rather than conditional grants from a higher authority to use one's freedom for the specified ends of man as a creature of God living in the fallen world.
The bottom line, which Kraynak posits in the beginning of the article, is that he wants to dispel the notion that traditional Christianity is naturally allied to republicanism/liberal democracy, in a way that it isn't to other illiberal undemocratic, non-republican forms of government:
This idea of an essential harmony, of course, goes back to the American founders, including John Witherspoon, as well as to Alexis de Tocqueville in the nineteenth century, and especially to the great Christian theologians of the last generation--Jacques Maritain, John Courtney Murray, Reinhold Niebuhr, and Dr. Martin Luther King, Jr. The political teaching of the last generation of theologians is especially clear: Christianity is naturally allied to liberal democracy in a way that it is not to monarchy or theocracy or communism.
As Kraynak notes, if Christians really wanted to rule nations to more effectively inculcate "Biblical principles" into society, they ought to choose a form of government that is less democratic, less republican, less "rights-oriented" (if the concept of "rights" should exist at all under such system), more hierarchical -- that is either monarchical or theocratic.
I would note under the system of liberal democracy/constitutional republicanism that America's Founders established, men like Kraynak or his evangelical Protestant counterparts have (or ought to have) every right to live their lives as conservative Christians. The concept of unalienable natural rights and republican government invariably frustrates their ability to use politics to force their vision of "the good" on pagans. And that's the way I prefer it.
Hearkening back to my post on the difference between "a-biblical" and "anti-biblical," the way I read Christianity and politics, an orthodox reading of the faith does not require Christians to use the political organs of the state try to force their vision of "the good" on pagans (though it doesn't prevent believers from doing so either). Indeed, the Bible seems focused almost entirely on spiritual, and little on political issues. That's why Christianity is compatible with a variety of forms of liberal and illiberal governments. That's why John Calvin who believed heretics should be executed and Roger Williams, who didn't, could both have teachings in line with the Bible, while supporting radically different concepts of religious liberty. And that's why the republican form of government that America's Founders established is more "a-biblical" than it is "anti-biblical."