This thesis explores the disciplinary relationship between natural philosophy (the study of nature or body) and theology (the study of the divine) in seventeenth-century England. Early modern disciplines had two essential functions. First, they set the rules and boundaries of argument – knowledge was therefore legitimised and made intelligible within disciplinary contexts. And second, disciplines structured pedagogy, parcelling knowledge so it could be studied and taught. This dual role meant disciplines were epistemic and social structures. They were composed of various elements, and consequently, they related to one another in a variety of complex ways. As such, the contestability of early modern knowledge was reflected in contestability of disciplines – their content and boundaries. Francis Bacon, Thomas White, Henry More and John Locke are the focus of the four chapters respectively, with Joseph Glanvill, Thomas Hobbes, other Cambridge divines, and a variety of medieval scholastic authors providing context, comparison and reinforcement. These case studies offer a cross-section of seventeenth-century thought and belief; they embody different professional and institutional interests, and represent an array of philosophical, theological and religious positions. Nevertheless, each of them, in different ways, and to different effect, put the relationship between natural philosophy and theology at the heart of their intellectual endeavours. Together, they demonstrate that, in seventeenth-century England, natural philosophy and theology were in flux, and that their disciplinary relationship was complex, entailing degrees of overlap and alienation. Primarily, natural philosophy and theology investigated the nature and constitution of the world, and, together, determined the relationship between its constituent parts – natural and divine. However, they also reflected the scope of man’s cognitive faculties, establishing which bits of the world were knowable, and outlining the grounds for, and appropriate degrees of, certainty and belief. Thus, both disciplines, and their relationship with one another, contributed to broad discussions about, truth, certainty and opinion. This, in turn, established normative guidelines. To some extent, the rightness or wrongness of belief and behaviour was determined by particular definitions of, and relationship between, natural philosophy and theology. Consequently, man’s place in the world – his relationship with nature, God and his fellow man – was triangulated through these disciplines.