If you study western literature and history, the topic of religion IS going to come up. I can't teach English without discussion/analysis/explanation of the religious history in America and how it influenced writing, particularly through the 1800's. And the constant biblical allusions do require some discussion. That isn't the same as expecting students to adhere to any particular religion. When I study eastern history or literature, I have to do some studying of eastern religions, etc. in order to gain fuller understanding of those texts also. That isn't going to force their beliefs on me either. It is just a set of knowledge that, like it or not, is a vital influence on all aspects of culture.