2. Historical Theology traces the development of the Biblical doctrines from the time of the apostles to the present day, and gives account of the results of this development in the life of the church.
By doctrinal development we mean the progressive unfolding and apprehension, by the church, of the truth explicitly or implicitly contained in Scripture. As giving account of the shaping of the Christian faith into doctrinal statements, Historical Theology is called the History of Doctrine. As describing the resulting and accompanying changes in the life of the church, outward and inward, Historical Theology is called Church History. Instance Cunningham's Historical Theology; Hagenbach's and Shedd's Histories of Doctrine; Neander's Church History. There is always a danger that the historian will see his own views too clearly reflected in the history of the church. Shedd's History of Christian Doctrine has been called “The History of Dr. Shedd's Christian Doctrine.” But if Dr. Shedd's Augustinianism colors his History, Dr. Sheldon's Arminianism also colors his. G. P. Fisher's History of Christian Doctrine is unusually lucid and impartial. See Neander's Introduction and Shedd's Philosophy of History.
3. Systematic Theology takes the material furnished by Biblical and by Historical Theology, and with this material seeks to build up into an organic and consistent whole all our knowledge of God and of the relations between God and the universe, whether this knowledge be originally derived from nature or from the Scriptures.
Systematic Theology is therefore theology proper, of which Biblical and Historical Theology are the incomplete and preparatory stages. Systematic Theology is to be clearly distinguished from Dogmatic Theology. Dogmatic Theology is, in strict usage, the systematizing of the doctrines as expressed in the symbols of the church, together with the grounding of these in the Scriptures, and the exhibition, so far as may be, of their rational necessity. Systematic Theology begins, on the other hand, not with the symbols, but with the Scriptures. It asks first, not what the church has believed, but what is the truth of God's revealed word. It examines that word with all the aids which nature and the Spirit have given it, using Biblical and Historical Theology as its servants and helpers, but not as its masters. Notice here the technical use of the word “symbol,” from συμβάλλω, = a brief throwing together, or condensed statement of the essentials of Christian doctrine. Synonyms are: Confession, creed, consensus, declaration, formulary, canons, articles of faith.
Dogmatism argues to foregone conclusions. The word is not, however, derived from “dog,” as Douglas Jerrold facetiously suggested, when he said that “dogmatism is puppyism full grown,” but from δοκέω to think, to opine. Dogmatic Theology has two principles: (1) The absolute authority of creeds, as decisions of the church: (2) The application to these creeds of formal logic, for the purpose of demonstrating their truth to the understanding. In the Roman Catholic Church, not the Scripture but the church, and the dogma given by it, is the decisive authority. The Protestant principle, on the contrary, is that Scripture decides, and that dogma is to be judged by it. Following Schleiermacher, Al. Schweizer thinks that the term “Dogmatik”should be discarded as essentially unprotestant, and that “Glaubenslehre” should take its place; and Harnack, Hist. Dogma, 6, remarks that “dogma has ever, in the progress of history, devoured its own progenitors.” While it is true that every new and advanced thinker in theology has been counted a heretic, there has always been a common faith—“the faith which was once for all delivered unto the saints” (Jude 3)—and the study of Systematic Theology has been one of the chief means of preserving this faith in the world. Mat. 15:13, 14—“Every plant which my heavenly Father planted not, shall be rooted up. Let them alone: they are blind guides” = there is truth planted by God, and it has permanent divine life. Human errors have no permanent vitality and they perish of themselves. See Kaftan, Dogmatik, 2, 3.
4. Practical Theology is the system of truth considered as a means of renewing and sanctifying men, or, in other words, theology in its publication and enforcement.
To this department of theology belong Homiletics and Pastoral Theology, since these are but scientific presentations of the right methods of unfolding Christian truth, and of bringing it to bear upon men individually and in the church. See Van Oosterzee, Practical Theology; T. Harwood Pattison, The Making of the Sermon, and Public Prayer; Yale Lectures on Preaching by H. W. Beecher, R. W. Dale, Phillips Brooks, E. G. Robinson, A. J. F. Behrends, John Watson, and others; and the work on Pastoral Theology, by Harvey.
It is sometimes asserted that there are other departments of theology not included in those above mentioned. But most of these, if not all, belong to other spheres of research, and cannot properly be classed under theology at all. Moral Theology, so called, or the science of Christian morals, ethics, or theological ethics, is indeed the proper result of theology, but is not to be confounded with it. Speculative theology, so called, respecting, as it does, such truth as is mere matter of opinion, is either extra-scriptural, and so belongs to the province of the philosophy of religion, or is an attempt to explain truth already revealed, and so falls within the province of Systematic Theology. “Speculative theology starts from certain a priori principles, and from them undertakes to determine what is and must be. It deduces its scheme of doctrine from the laws of mind or from axioms supposed to be inwrought into its constitution.” Bib. Sac., 1852:376—“Speculative theology tries to show that the dogmas agree with the laws of thought, while the philosophy of religion tries to show that the laws of thought agree with the dogmas.” Theological Encyclopædia (the word signifies “instruction in a circle”) is a general introduction to all the divisions of Theology, together with an account of the relations between them. Hegel's Encyclopædia was an attempted exhibition of the principles and connections of all the sciences. See Crooks and Hurst, Theological Encyclopædia and Methodology; Zöckler, Handb. der theol. Wissenschaften, 2:606–769.
The relations of theology to science and philosophy have been variously stated, but by none better than by H. B. Smith, Faith and Philosophy, 18—“Philosophy is a mode of human knowledge—not the whole of that knowledge, but a mode of it—the knowing of things rationally.” Science asks: “What do I know?” Philosophy asks: “What can I know?” William James, Psychology, 1:145—“Metaphysics means nothing but an unusually obstinate effort to think clearly.” Aristotle: “The particular sciences are toiling workmen, while philosophy is the architect. The workmen are slaves, existing for the free master. So philosophy rules the sciences.” With regard to philosophy and science Lord Bacon remarks: “Those who have handled knowledge have been too much either men of mere observation or abstract reasoners. The former are like the ant: they only collect material and put it to immediate use. The abstract reasoners are like spiders, who make cobwebs out of their own substance. But the bee takes a middle course: it gathers its material from the flowers of the garden and the field, while it transforms and digests what it gathers by a power of its own. Not unlike this is the work of the philosopher.” Novalis: “Philosophy can bake no bread; but it can give us God, freedom and immortality.” Prof. DeWitt of Princeton: “Science, philosophy, and theology are the three great modes of organizing the universe into an intellectual system. Science never goes below second causes; if it does, it is no longer science—it becomes philosophy. Philosophy views the universe as a unity, and the goal it is always seeking to reach is the source and centre of this unity—the Absolute, the First Cause. This goal of philosophy is the point of departure for theology. What philosophy is striving to find, theology asserts has been found. Theology therefore starts with the Absolute, the First Cause.” W. N. Clarke, Christian Theology, 48—“Science examines and classifies