2. As regards the relation of the History of Doctrines to other branches of theological science, it is evidently a subdivision of Church history, separately treated on account of its special importance for theologians, and on account of its wide ramifications. It presupposes Biblical theology as its basis (or as its first period). As it recounts the formation and contents of public confessions of faith, and the distinguishing principles set forth in them, it forms itself the basis of symbolics, or comparative dogmatic theology, which stands to it in the same relation as Church statistics of any particular period stand to the advancing history of the Church. As the opinions of the prominent, especially the earliest, fathers of the Church are of considerable importance in the history of any Christian doctrine, it has frequently occasion to refer to the results of Patristics (q.v.). Of the "history of Heresies," the beginning will always have to be noticed in a comprehensive history of doctrine; its further progress only in so far as the heresies remain of importance for the Christian world at large. To a "general history of religion" it may have occasionally to refer; and with the, history of philosophy and the history of Christian ethics it may sometimes have to travel over the same ground, though in the latter case it will treat the same subjects from a different point of view. Archaeology, and the sciences auxiliary to Church history, such as universal history, ecclesiastical philology, ecclesiastical chronology, diplomatics, etc., also aid in furnishing materials.
3. The value of the History of Doctrines, in a scientific point of view, is evident. Though the history of no doctrine can have a decisive influence in determining the faith of an evangelical theologian, who to this end searches the Bible exclusively, it is for him the most important portion of the history of the Christian Church, leads him into a more minute contemplation, and frequently into a deeper insight of Biblical doctrines, and furnishes him with powerful weapons, both apologetic and polemic, against the various forms of error.
4. The periods of the history of doctrines have been differently determined by the writers on the subject. Hagenbach assumes the following five periods:
1. The Age of Apologetics, from the close of the apostolic age to the death of Origen (A.D. 80-254).
2. The Age of Polemics, from the death of Origen to John Damascenus (254-730).
3. The Age of Systems, from John Damascenus to the Reformation (Scholasticism in its widest sense) (730-1517).
4. The Age of Polemico-ecclesiastical Symbolism (the conflict of confessions), from the Reformation to the rise of the Philosophy of Leibnitz and Wolf in Germany (1517-1720).
5. The Age of Criticism, of Speculation, and of the antagonism between Faith and Knowledge, Philosophy and Christianity, Reason and Revelation, including the attempts to reconcile them, from the year 1720 to the present day. Neander's division is:
1. To Gregory the Great.
2. To the Reformation.
3. From the Reformation to the present time.
Minscher, Engelhardt, and Meier adopt the division into Ancient, Mediaeval, and Modern times. Klee (Romans Cath.) coincides almost With Hagenbach.
Baumgarten-Crusius (Rationalist) adopts in his Compendium six periods:
1. To the Council of Nice; Formation of the System of Doctrines by reflection and opinion.
2. To the Council of Chalcedon; Formation by the Church.
3. To Gregory VII; Confirmation of the System by the Hierarchy.
4. To the end of the 15th century; Confirmation by the Philosophy of the Church.
5. To the beginning of the-18th century; Purification by Parties.
6. To the present time; Purification by Science. Kliefoth (High-Church Lutheran) divides as follows:
1. Age of Formation of Doctrines