“The Two Heads of the Eagle”: Aquinas and Rousseau on Civil Religion

WHEN PRESIDENT Barack Obama spoke in Cairo in October 2009, he uttered a surprising statement: “faith should bring us together.” The statement was surprising first because he was speaking in a region plagued by interreligious conflict: faith would seem to be pulling the Middle East apart. But the statement was also surprising because the president was speaking on behalf of the secular and liberal West. Why would he champion the role of faith in the effort toward peace?

President Obama’s words underscore the complexities of our age.¹ The ambiguities of secularism have often led to more rather than to less religious conflict in politics, and in many parts of the world secularism simply never arrived. Indeed, Jürgen Habermas has suggested that liberalism cannot articulate sufficient moral foundations for itself in the face of such threats, warning that liberalism needs to cooperate with at least some forms of religion.² Perhaps it is not surprising, then, that scholars have lately reconsidered a strand of modern thought that does not share liberalism’s commitment to separating religion from politics.³ It has in fact turned to religion as a source of public values and legitimacy. This is civil religion. As the “political use of religion,” civil religion is as ancient as politics itself.⁴ Yet civil religion has developed a new task in modernity: to domesticate religion. Moreover, in its attempts to reckon with religious pluralism in early modern Europe, civil religion has at times served as a dialogue partner and competitor with liberalism.

Yet their differences are considerable. Whereas classical liberalism seeks to ground political obligation in non-controversial conceptions of the good, civil religion embraces religious norms and practices as politically binding. Civil religion grounds the particular of a political community in another particular, namely, religion.⁵ Civil religion thereby runs counter, both to liberalism’s commitments to rationalism and universalism, and to its distinction between religion and politics.⁶

The connection between civil religion and liberalism comes to the fore in the work of Ronald Beiner, whose recent studies of civil religion have clarified the origins and goals of liberalism.⁷ In illuminating the central place of Rousseau in framing the role of civil religion in modernity, Beiner has shown how much civil religion and liberalism share against theocratic visions of politics. Yet he also equates religion with theocracy, accepting the illiberal premise of civil religion that religion is necessarily a problem that must be neutralized—what Charles Taylor calls a “subtraction story.”⁸

Subverting Rousseau and Beiner, I argue that at least one religion, Christianity, can intervene in politics and thereby critically support it without becoming theocratic. Like liberalism, Christianity recognizes a distinction between the earthly and the spiritual. That distinction is not without its tensions, however, and such tensions are at the heart of navigating politics. But Christianity can direct the liberal polity away from facile resolutions of those tensions, and so fulfil Habermas’s hopes for a religious dialogue partner for liberalism.

In this article, I turn to Thomas Aquinas to illuminate such possibilities. In a little-studied work, De regno, he treats civil religion thematically, a treatment that is in many ways the high point of the text. He details both why Christianity cannot be a civil religion and yet why it must remain politically active. In his work we will see both a challenge for liberalism to take its own principles seriously, and a recognition that religion and liberal politics can be aligned in their goal against civil religion and theocracy. Yet Aquinas also cautions that religion and politics can come to no easy settlement, a lesson which should dissolve any complacency on liberal or civil-religious terms about the possibility of achieving a lasting institutional resolution to their relationship.

In what follows, I juxtapose the arguments of Rousseau and Aquinas to bring them into conversation. After detailing Rousseau’s account of civil religion, I describe De regno in two movements: the starkly political treatment of book I, and the more theological account of book II. I then bring...