The second part of the Summa begins with a prologue which outlines the purpose and scope of what is now called moral theology. Hence we dwell here, first on the nature of moral theology, and secondly on its divisions. The word "image" (in the phrase "image of God") signifies man as endowed with intellect, free will, and self-mastery. Hence. having treated of God, who is man's exemplar. we now proceed to consider God's image. man. namely, who is the source of his own deeds. since he has free will and mastery of self. What a sublime conception of moral theologyl God's liberty in creation is the prototype of man's free activities. In the first part of the Summa, the Saint. treating of God's creatures, had shown how man is the imperfect image of God, since, like God, man can know and love himself. Thus representing not only the divine nature, but also the divine Trinity. Now he proceeds to show that man is God's image, not only by his higher faculties, but also in his free activities. whereby he knows and loves not only himself, but also God, as God knows and loves Himself. This knowledge and love are indeed the final goal of all human life. But even here on earth a saint differs from his fellows by that love wherewith he loves not only himself, but God. From this sublime viewpoint moral theology is the science of imitating God. It produces a more and more perfect likeness of man to God. And this likeness would be man's goal even if God had not become man. But how much more perfect is this likeness when imitation of God has become imitation of Christ. A more scholastic description of moral theology can be found in the first part: : I "Although theology is more speculative than practical, it is nevertheless practical, in its treatment of human acts, by which man is led to perfect knowledge of God wherein lies eternal blessedness." Again, in the second question, outlining the entire Summa, he says: "We will speak first of God, secondly of man's journey to God, thirdly of Christ who, as man, is our road to God." Thus moral theology may be defined as that part of theology which, guided by revelation, studies human acts as the road to man's supernatural goal. Or, more briefly: a theological treatise which guides human acts to man's supernatural goal. Moral theology, then, stands on a higher level than natural ethics. Natural ethics guides man to his last natural goal, which consists, not in the beatific vision and supernatural love, but in the knowledge, perfect but abstract, of God as the author of nature, and in the consequent natural love of God above all else. Ethics, properly speaking, does not deal with man as the image of the triune God. In the definition given above, many theologians avoid the phrase "that part of theology," substituting for it "that branch of knowledge." Hence arises the following question: Does moral theology differ specifically from dogmatic theology?