What is the relationship between Carl Schmitt's political theology and Christianity? Was Schmitt a Catholic, Protestant, Gnostic, Marcionist, atheist, or just an occasional opportunist? Schmitt is one of the most influential and controversial political theorists of the twentieth century, and his political theology continues to be the object of heated debates among scholars. Considering his early writing, Schmitt appears to be a Catholic thinker concerned with the public role of the Church in modern societies. However, after the publication of his Political Theology and his work on the phenomenon of secularization, some of his contemporaries, including his former friend and theologian Erik Peterson, began to point out the contradiction between his ideas and the Christian revelation. In Schmitt's Concept of the Political, for instance, he uses Christian themes and biblical references to legitimize his concept of the political as the distinction between friends and enemies. Based on the fall of man and the doctrine of original sin, Schmitt concludes that any serious political theory must presuppose man to be evil by nature. Thus, the only form of restraining human hostility is through the identification of an external enemy, which would allow the strengthening of the internal ties of friendship and the establishment of internal peace. To achieve this internal stability, Schmitt develops his concept of the "total state," which seeks to subordinate all indirect powers of the society to the sovereign. As the sovereign protects the community from hostility, Schmitt's interpretation of Hobbes's Leviathan argues that the state should become a unity of will and spirit. Consequently, no internal or external profession of faith outside the official religion of the state should be allowed, because it would delegitimize the power of the sovereign and allow the appearance of indirect powers. After World War II, Schmitt continues his political theological speculations to uncover a deeper meaning of human history. This time, however, he finds in Saint Paul's Second Letter to the Thessalonians the concept of the katechon [restrainer], who has the historical mission of containing the appearance of the antichrist and the spirit of iniquity. These constant references to Christian themes have led many contemporary scholars to reassess Schmitt's political theology and to consider it as evidence of his faith in divine revelation. Nevertheless, this position contrasts sharply with Peterson's critique, which suggests that Schmitt's ideas have heretical, and even pagan, overtones. To assess this problem, the purpose of this dissertation is to clarify Schmitt's concept of political theology and its relationship with Christianity. It will further explore his appropriation of biblical language and narrative to comprehend whether he uses religious language to give a consistent account of its political relevance or to justify his political position.