Harnack's insights into the "what" of Christianity from a scholarly, not a theological point of view from any denomination, surprises the reader with keen insights from that period. Adolf von Harnack (1851-1930) was a German theologian and prominent church historian. This book contains Harnack's lectures that were originally given during the 1899-1900 winter semester at the University of Berlin. For Harnack, "the Christian religion is something simple and sublime; it means one thing and one thing only: Eternal life in the midst of time, by the strength and under the eyes of God." He suggests, "either the Gospel is in all respects identical with its earliest form, in which case it came with its time and has departed with it; or else it contains something which, under differing historical forms, is of permanent validity."