https://pubmed.ncbi.nlm.nih.gov/15990520/In clinical practice, no clear guidelines exist to distinguish between "normal" religious beliefs and "pathological" religious delusions. Historically, psychiatrists such as Freud have suggested that all religious beliefs are delusional, while the current DSM-IV definition of delusion exempts religious doctrine from pathology altogether. ....
Religious beliefs and delusions alike can arise from neurologic lesions and anomalous experiences, suggesting that at least some religious beliefs can be pathological. Religious beliefs exist outside of the scientific domain; therefore they can be easily labeled delusional from a rational perspective.....
The question for debate is stated in the title, Are Religious Beliefs Delusional?
A subordinate question: Should we distinguish between a learned belief in supernatural phenomena and those who believe and attribute their beliefs to personal experience... and how could we tell?