churchgoer vs religious person

churchgoer and religious person both are nouns.

Word	Noun	Adjective	Verb	Adverb
churchgoer	Yes	No	No	No
religious person	Yes	No	No	No

As nouns, religious person is a hypernym of churchgoer; that is, religious person is a word with a broader meaning than churchgoer:

churchgoer (noun)	religious person (noun)
a religious person who goes to church regularly	a person who manifests devotion to a deity