How to establish the authoritative nature of one's interpretation of Scripture represented a central challenge for any Protestant theologian during the sixteenth century. This edited volume, which contains nine analytical essays complemented by an introduction and conclusion, examines this issue by focusing on the various non-Scriptural sources that theologians employed to validate their claims to doctrinal authority. In this capacity, The search for authority fits into a growing historiographical trend of works that analyse the extent to which early reformers appealed to written sources other than Scripture in support of their arguments. The volume's chapters address thinkers on the continent as well as in England, with a heavy emphasis on Protestant theologians. Two of the essays also examine Catholic discussions of ecclesiastical authority before and after Trent. Taken as a whole, this collection encourages us to move beyond the idea of sola scriptura to understand what other sources theologians used when Scriptural insight was incomplete or lacking on a certain issue. The book's various studies display the diversity of sources used by authors across the confessional spectrum, from patristic texts to medieval tomes to new views on the course of church history. They also show how, as consensus over who had authority to interpret Scripture broke down, the ability to compromise also broke down, as different authors employed different sources, even different approaches to the same sources, that lacked a common ground. Appeals to the Church Fathers, sometimes on different sides of the same issue, were particularly widespread and important. The essays in this volume speak to the range of ways in which sixteenth-century theologians sought to establish the precedence of their arguments over competing ideas. Those scholars interested in sixteenth-century theology, the legacy of patristic thinkers during the Reformation, and the influence of polemic on doctrinal thought will find these essays valuable.