Word of God vs Holy Writ

Word of God and Holy Writ both are nouns.

Word	Noun	Adjective	Verb	Adverb
Word of God	Yes	No	No	No
Holy Writ	Yes	No	No	No

As nouns, Word of God and Holy Writ are synonyms defined as:

Word of God and Holy Writ: the sacred writings of the Christian religions

Other synonyms of Word of God include Bible, Book, Christian Bible, Good Book, Holy Scripture, Scripture, Word.

Word of God (noun)	Holy Writ (noun)
the sacred writings of the Christian religions	the sacred writings of the Christian religions
the message of the Gospel of Christ
a manifestation of the mind and will of God