Gospel vs Gospels

Gospel and Gospels both are nouns.

Word	Noun	Adjective	Verb	Adverb
Gospel	Yes	No	No	No
Gospels	Yes	No	No	No

As nouns, Gospel and Gospels are synonyms defined as:

Gospel and Gospels: the four books in the New Testament (Matthew, Mark, Luke, and John) that tell the story of Christ's life and teachings

Other synonyms of Gospel include evangel.

Gospel (noun)	Gospels (noun)
the four books in the New Testament (Matthew, Mark, Luke, and John) that tell the story of Christ's life and teachings	the four books in the New Testament (Matthew, Mark, Luke, and John) that tell the story of Christ's life and teachings