How can you study the properties of something you don't believe exists?
Edit: People are downvoting this, but I genuinely want to know how "theology is the study of supernatural things" and "theology does not rely on belief in the supernatural" are not in complete contradiction.
Religious faith from certain perspectives is something like: choosing to believe despite being unable to comprehend with your rational mind. That's the basic core of the inquiry, you start from there and see what happens.
Edit: People are downvoting this, but I genuinely want to know how "theology is the study of supernatural things" and "theology does not rely on belief in the supernatural" are not in complete contradiction.