First Epistle to the Corinthians vs Epistle

First Epistle to the Corinthians and Epistle both are nouns.

Word	Noun	Adjective	Verb	Adverb
First Epistle to the Corinthians	Yes	No	No	No
Epistle	Yes	No	No	No

First Epistle to the Corinthians (noun)	Epistle (noun)
a New Testament book containing the first epistle from Saint Paul to the church at Corinth	a book of the New Testament written in the form of a letter from an Apostle