Theology is critical scholarship.
It is not advocacy on behalf of Christianity. It is an endeavour supported by those churches who believe that there is something to be gained by open, critical analysis. Theology can be a controversial discipline. It sometimes faces distrust from who are averse to critical thought and it sometimes faces prejudice from those who lump together anything to do with Christianity as unserious. The majority of students who study theology do so because of prior commitment to Christianity and its values, but there are also students who do theology without any such commitment.