Religious Studies
Religious studies, alternately known as the study of religion, is an academic field devoted to research into religious beliefs, behaviors, and institutions. It describes, compares, interprets, and explains religion, emphasizing systematic, historically based, and cross-cultural perspectives.
Theology
All significant concepts of the modern theory of the state are secularized theological concepts not only because of their historical development - in which they were transferred from theology to the theory of the state, whereby, for example, the omnipotent God became the omnipotent lawgiver-but also because of their systematic structure, the recognition of which is necessary for a sociological consideration of these concepts. The exception in jurisprudence is analogous to the miracle in theology. Only by being aware of this analogy can we appreciate the manner in which the philosophical ideas of the state developed in the last centuries.
Carl Schmitt, Political Theology (1922; 1934), Ch. 3. Political Theology; translated by George Schwab.