Those are two topics that everyone takes seriously, other than the uninformed and ignorant.
You'd be hard pressed to find someone who would change their religious or political ideas because someone pointed out something wrong with their beliefs. That can cause major animosity because people will not change their religious or political beliefs at the drop of a hat.
Religion and politics are two of the main things that shape our world and people spend a lot of time deciding which religion/political group to support, and by others undermining their choices by trying to change their views, it will inevitably lead to an uncomfortable situation.