This post is part of an ongoing series reflecting on the appropriate approach to and method for historical theology.
Building upon the methodological principles I have been outlining, I wish to briefly offer some of the operating assumptions of my work in historical theology. Historical theological study must always engage other voices and perspectives—there is no such thing as a “stand alone” presentation of the past. Engagement with other voices is generally most fruitful when assumptions and methodologies—those structures standing behind historical constructions—are engaged. History is different than the “lived past”, although historical theology can partially, perspectivally, and humbly speak about the past. The historical past, when invoked in the present, is always influenced by the purposes of the present. This is not to say that meaningful perspectives on the past cannot be offered, only that the context of the present influences any appeal to the past. Historical theology requires an ordered and academically rigorous approach, willing to investigate and engage truth claims of all types and origins, including those undertaking study of the Christian past. Texts remain the primary basis for historical theological work, and are to be considered within their broad historical, theological, social, linguistic, and literary contexts. Finally, historical theology must be understood as the integration of history and theology, the rigorous intellectual methodology of the study of the past—complete with its problematizations of language and context—combined with the humble practice of seeking understanding of a transcendent God and His action in the world.
This dual focus on history and theology remains imperative for effective historical theological practice. Only from a methodologically informed foundation that consistent historical work may be launched. Valuable historical inquiry takes place in the context of conversation with other voices and perspectives. To know where you are, one must first understand from where you have come. Operating assumptions and philosophical presuppositions shape worlds. These concepts necessitate interaction with the ideas and concepts which have shaped methodological discourse if one is to successfully offer anything of value for the Church or Academy. Similarly, historical theology must be grounded in a foundation of theology, that true history and knowledge are reflections of the Truth of God. This is where historical theology and general historical practice are radically different: where history encounters methodological problems in appealing to overarching narratives or transcendence of any type, historical theology can comfortable integrate the insights of faith and reason.
 Gerrish, 291-2.