Very quickly I'll give my two cents. You are a government official, with the duty to issue marriage licenses to citizens. You are now representing the government in this issue, and it is your duty as a government official to issue these licenses within the confines of the law. Am argument I like for comparison is; what if the county you live in is a "shall issue" county; meaning you shall be issued a concealed carry permit as long as you pass the legal requirements. But the official who issues the permits believes guns shouldn't be in the hands if citizens and refuses to issue said permits. Should they be reprimanded for refusing to follow through with their job due to personal beliefs? Yes. Like I said, you are then representing the government, you are no longer representing your personal beliefs.