An introduction to the study of systematic theology. Hagenbach has segregated his doctrines into five periods, the first entitled "From the Apostolic Age to the death of origen," the fifth being "The Age of Criticism, or Speculation, and of the antagonism between faith and knowledge, philosophy and Christianity, reason and revelation; and attempts to reconcile these antagonisms."

The Historical Volume of what was originally called Reformed Dogmatics now appears with a new title, namely, History of Christian Doctrines. Works on the gradual development of theological truth in the Church of Jesus Christ usually appear alongside of those which deal with the systematic reproduction of it, and thus stand out as separate works. It was thought best to follow this practice, since this will stress the fact that, after all, the history of the development of Christian thought in the Church is a separate study.