I make no apology for the homiletical element in my book. To be either true or useful, theology must be a passion. _Pectus est quod theologum facit_, and no disdainful cries of “Pectoral Theology!” shall prevent me from maintaining that the eyes of the heart must be enlightened in order to perceive the truth of God, and that to know the truth it is needful to do the truth. Theology is a science which can be successfully cultivated only in connection with its practical application. I would therefore, in every discussion of its principles, point out its relations to Christian experience, and its power to awaken Christian emotions and lead to Christian decisions. Abstract theology is not really scientific. Only that theology is scientific which brings the student to the feet of Christ. I would hasten the day when in the name of Jesus every knee shall bow. I believe that, if any man serve Christ, him the Father will honor, and that to serve Christ means to honor him as I honor the Father. I would not pride myself that I believe so little, but rather that I believe so much. Faith is God’s measure of a man. Why should I doubt that God spoke to the fathers through the prophets? Why should I think it incredible that God should raise the dead? The things that are impossible with men are possible with God. When the Son of man comes, shall he find faith on the earth? Let him at least find faith in us who profess to be his followers. In the conviction that the present darkness is but temporary and that it will be banished by a glorious sunrising, I give this new edition of my “Theology” to the public with the prayer that whatever of good seed is in it may bring forth fruit, and that whatever plant the heavenly Father has not planted may be rooted up. ROCHESTER THEOLOGICAL SEMINARY, ROCHESTER, N. Y., AUGUST 3, 1906. PART I. PROLEGOMENA. Chapter I. Idea Of Theology. I. Definition of Theology. Theology is the science of God and of the relations between God and the universe. Though the word “theology” is sometimes employed in dogmatic writings to designate that single department of the science which treats of the divine nature and attributes, prevailing usage, since Abelard (A. D. 1079-1142) entitled his general treatise “Theologia Christiana,” has included under that term the whole range of Christian doctrine. Theology, therefore, gives account, not only of God, but of those relations between God and the universe in view of which we speak of Creation, Providence and Redemption.