田立克文化神學的「關聯法」，其實是對西方源自古典希臘哲學「辯證法」的應用與轉化。然而，辯證法在德國古典哲學的發展中，特別是在面對歷史與實存的態度上，已與古希臘不同。例如謝林晚期的思想，特別是對於「惡的實存」與人類「自由」的分析，代表著從著重理論性的唯心論辯證，轉向了重視實存性的唯實論辯證。海德格肯定謝林的自由論分析，以及他接納有限實存的積極態度。這兩者對田立克文化神學的存有論方法皆有影響。簡言之，田立克宗教哲學的方法就是辯證綜合。其宗教哲學的目的，就是在辯證綜合中，整合「啟示」與「理性」。而田立克最大的貢獻在於，他將傳統宗教哲學的方法，從抽象觀念與邏輯體系的驗證，拉向具體實存以及對無條件意義的動態性歷史闡述。

To make a survey of the methodology in Paul Tillich's theology of culture, we find that his method of correlation was the application and transformation of dialectical method, which originated from ancient Greece. However, the development of dialectic in classical German philosophy, particularly the attitude towards history and reality, was different from the Hellenism. For instance, in late Schelling's philosophy, especially in the analysis of the relation between the evil existence and the human freedom, idealism shifted to realism. Martin Heidegger affirmed Schelling's analysis of free, and the positive attitude of the acceptance of finite reality. Tillich's theology of culture was deeply influenced by Schelling and Heidegger. In short, the feature of Tillich's philosophy of religion was dialectical synthesis. He devoted to integrate human reason and revelation in the dialectical way, and his accomplishment was that he turned his method of philosophy of religion to the concrete reality and the vital process of seeking unconditional meaning in the interpretation of history.