I had a philosophy professor who believed evolution was 'just a theory', and routinely dismissed it. I don't think she was religious either. Then again, I had another philosophy teacher who taught logic, which is the most pure use of right/wrong that I can think of.
evolution IS 'just a theory'. like relativity and other scientific theories. it is just a coherent framework to explain observations. today it is our best theory, tomorrow it may not be. you cannot say that evolution is Truth. Truth exists only in mathematics, logics etc.