This chapter outlines the theo-political conditions under which the English marriage plot was established. It shows how a particular party faction, the Court Whigs – which was committed both to a view of church-state relations that I call Erastian and to a particular understanding of natural law – reformed the regulation of marriage. Yet these efforts immediately met with contestation, much of which was based on alternative understandings of natural law and, implicitly, of church-state relations too. In the welter of debate triggered by the legislation, marriage was viewed as central not just to the polity but also to the divine order.