.Scripture alone; the watchword of the Reformation in its establishment of the basis for a renewed and reformed statement of Christian doctrine. We find the concept of sola Scriptura, Scripture alone as the primary and absolute norm of doctrine, at the foundation of the early Protestant attempts at theological system in the form of exegetical loci communes (q.v.), or common places. In the orthodox or scholastic codification of Lutheran and Reformed doctrine, the sola Scriptura of the Reformers was elaborated as a separate doctrinal locus placed at the beginning of theological system and determinative of its contents. Scripture was identified as the principium cognoscendi, the principle of knowing or cognitive foundation of theology, and described doctrinally in terms of its authority, clarity, and sufficiency in all matters of faith and morals. Finally, it ought to be noted that sola Scriptura was never meant as a denial of the usefulness of the Christian tradition as a subordinate norm in theology. The views of the Reformers developed out of a debate in the late medieval theology over the relation of Scripture and tradition, one party viewing the two as coequal norms, the other party viewing Scripture as the absolute and therefore prior norm, but allowing tradition a derivative but important secondary role in doctrinal statement. The Reformers and the Protestant orthodox held the latter view, on the assumption that tradition was a useful guide, that the trinitarian and christological statements of Nicaea, Constantinople, and Chalcedon were expressions of biblical truth, and that the great teachers of the church provided valuable instruction in theology that always needed to be evaluated in the light of Scripture. We encounter, particularly in the scholastic era of Protestantism, a profound interest in the patristic period and a critical, but often substantive, use of ideas and patterns enunciated by the medieval doctors.
 Richard A. Muller, Dictionary of Latin and Greek Theological Terms : Drawn Principally from Protestant Scholastic Theology (Grand Rapids, Mich.: Baker Book House, 1985), 284.