To rescue
You asked R D Teitelbaum to cite a verse which teaches that one can’t talk about other religions. Dev 17:11 states that we must follow the dictates of our Rabbis. With this verse Hashem empowered the Rabbis to make laws for the people which must be followed. To that point, Rabbi Akiva said that one who studies Sefarim Chitzonim is an Apikorus. There are other such teachings which prohibit studying other religions. So yes, there is a valid source. Now why don’t you provide a source for your belief that G-d doesn’t expect us to keep His laws?