Roger Williams (1603–83), the founder of Rhode Island, has long been a favoured subject for historians of colonial American politics and religion. Williams staunchly espoused the separation of church and state in an era when almost all of his contemporaries assumed that an established church provided the only safe foundation for an ordered society. In his most famous book, The Bloudy Tenent of Persecution (1644), Williams advocated religious liberty and made the case that it should extend to Roman Catholics, Jews and Muslims, a position that was even more expansive than John Locke's later argument for toleration. But, despite the interest of historians, Roger Williams has received virtually no attention from theologians and ethicists, even though his views have clear implications for ethics in a context of religious diversity. Hence, The Moral Theology of Roger Williams by James Calvin Davis brings a fresh perspective to scholarly interpretation of Williams and his legacy to American public life.

A principal reason, perhaps, that Williams has not previously attracted attention from theologians is that he did not directly address any traditional questions of systematic theology or classic concepts of theological ethics. Williams took up the vocation of theological controversy and, apart from one devotional tract, all of his writings engaged specific debates: about the work of the Westminster Assembly of Divines, about the nature of the ministry, about Quaker evangelism and, especially, about ‘soul liberty’. In order to provide a context for theological consideration of Williams' writings, therefore, Davis begins by describing Williams as a theologian from the Puritan wing of the Reformed tradition. Although describing Williams as a Reformed theologian is nothing new to American religious historians, it enables Davis to take comments on Christology, conscience or human nature out of their polemical setting in Williams' tracts and resituate them in a broad theological conversation extending from John Calvin, William Perkins and William Ames to Karl Barth, Stanley Hauerwas and James M. Gustafson.

This method is not without its hazards. It may collapse the distinction between background presuppositions and explicit theological argument, or it may misleadingly consolidate ideas that are superficially related but actually function in quite different theological arguments. For example, Davis proposes in his second chapter that, ‘for Williams, the incarnation of Christ was vital to a proper understanding of the moral life from a Christian perspective’ (p. 23). However, Williams gave virtually no attention to the doctrine of the incarnation. Unlike the nineteenth-century American Reformed theologian John Williamson Nevin, for whom the incarnation was the governing principle for an entire theological system, Williams talks about Jesus Christ in a variety of ways that sometimes stress the historicity of Jesus, sometimes his importance as a moral teacher and sometimes his eschatological return. To draw all this together as representing an incarnational theology seems, to this reviewer, a bit of a stretch.

Davis' real contribution, however, lies not in the history of theology but in the way he reappropriates Roger Williams for contemporary conversations about the relation between Christian conviction and public ethics. Davis effectively argues that Williams provides significant resources for ethicists who desire to make ‘a meaningful contribution to public discourse’ while maintaining ‘a commitment to the distinctiveness of Christian ethics’ (p. 117). To accomplish this reappropriation, Davis first demonstrates that Williams drew from the tradition of natural law, in order to make the case for the possibility of a common morality. Williams believed that rational deliberation gave humans ‘access to natural law’, and he employed ‘historical analysis of human experience’ as a ‘tool for the practical deliberation of moral norms and values’ (p. 65). Davis could amplify this point by a more thorough analysis of the relation of the Decalogue to natural law in the Reformed tradition (pp. 60, 103), especially Williams' analysis of the relationship between the ‘two tables’ of the law, duties owed to God and duties to humanity.

Davis follows his analysis of natural law with two excellent chapters that interpret the concepts of conscience and civility in the writings of Roger Williams. Beginning with Williams' historical observation that many kingdoms have flourished without any knowledge of Christianity, the notions of conscience and civility emphasise that the stability of civil society requires not only civil cooperation and mutual accountability but also tolerance for principled ethical and religious differences. Thus, in a famous metaphor, Williams declared that the commonwealth was a ship with a very diverse crew, which must nonetheless make sail for port. Throughout this analysis, Davis strongly advocates a fresh consideration of Williams' theological ethics, and he does so with a critical balance that makes Williams a conversation partner rather than merely an icon.