To Tillich, theology is required to serve the needs of the Christian Church. This involves both stating the truth of the Christian message and providing a satisfactory interpretation of this truth for each generation. Systematic Theology establishes a close correlation with philosophy through the organisation of subject matter in each section. The main theological problems discussed illustrate the systematic consequences of this correlation. Tillich does not deal with all the traditional problems of a theological system and the work does not make extensive reference to the Bible or to classical theologians. Systematic Theology aims, rather, ‘to set out the method and structure of a theological system from an apologetic point of view in continuous correlation with philosophy’.