In this book, I will address changes over time to Reformed Protestant conceptions of natural law. This exercise is significant because, I contend, these changes contributed to the desacralisation of theories of the origins of political life. This desacralisation contributed to a further phenomenon: the secularisation of political thought during the sixteenth and seventeenth centuries. When early Reformed Protestant figures wrote about natural law, they tended to do so in a way that was reflective of the scholastic and Aristotelian inheritance from medieval theology, philosophy and jurisprudence. God governed the universe, in part through the natural law. Humans were naturally social and political, and therefore human political life was part of God's creation order. It was a theistic foundation for politics. This changed when the emphasis in theories of natural law shifted from a theistic basis to an anthropocentric basis. Certain Reformed thinkers, some of whom were extremely influential on the shaping of western political philosophy, based their understanding of the law of nature upon human self-preservation, rather than on God. At the same time, these thinkers conceived of political existence as an artifice, rather than divinely created. If the law of nature did not issue from God, then any human political disposition reflective of human nature must be artificial. Therefore, political life was also desacralised. Here, we see the emptying of the sacred from politics.

A contemporary application lies fallow in this historical argument. The secularisation of anything, let alone something as important as politics, is likely to have consequences. Readers attuned to questions about the viability and vitality of liberal democracy might have come across certain critiques of the secular roots, and secular horizon, of political liberalism. While this intellectual history does not directly address the religious roots of liberalism, the findings and conclusion do raise a question about whether the roots of liberalism were unstable from the beginning. Perhaps something could be amiss in the dominant western political ideology of the nineteenth, twentieth and twenty-first centuries. Some scholars and commentators look to the theoretical to explain liberalism's apparent weakness. Others look to history.

James Davison Hunter, for instance, argues that the emergence of a secular understanding of political life lies at the heart of the instability of liberalism. Core to the cultural logic of liberal democracy is what Davison Hunter calls the ‘fragile … synthesis of Reformed and Enlightenment traditions’.