When is a Religious Belief Delusional?

[Angrboda]

That doesn't really answer the question.  They can be both and both are the same, or they can be both and yet being delusional entails something more than simply being wrong.  If it's the latter, then what is that something more that makes a person delusional?  If not, why use a term that is perceived as insulting when there is a non-insulting synonym?

It answers the question for me. What synonym do you suggest that I use? You can be wrong without a belief, delusion includes the belief.

The definition of a belief is an acceptance of something as true or that something exists. How can you be wrong without holding something as true?

Synonyms are: wrong, mistaken, in error, incorrect. But that doesn't answer the question either. You're free to do what you like, I'm questioning whether you have good reason to use the term delusion. Everything you're saying, in addition to your cheek, suggests to me the answer to that question is no.