Epistle to the Philippians vs Epistle of Paul the Apostle to the Philippians

Epistle to the Philippians and Epistle of Paul the Apostle to the Philippians both are nouns.

Word	Noun	Adjective	Verb	Adverb
Epistle to the Philippians	Yes	No	No	No
Epistle of Paul the Apostle to the Philippians	Yes	No	No	No

As nouns, Epistle to the Philippians and Epistle of Paul the Apostle to the Philippians are synonyms defined as:

Epistle to the Philippians and Epistle of Paul the Apostle to the Philippians: a New Testament book containing an epistle from Saint Paul to the church at Philippi in Macedonia

Other synonyms of Epistle to the Philippians include Philippians.

Epistle to the Philippians (noun)	Epistle of Paul the Apostle to the Philippians (noun)
a New Testament book containing an epistle from Saint Paul to the church at Philippi in Macedonia	a New Testament book containing an epistle from Saint Paul to the church at Philippi in Macedonia