Scripture vs sacred writing

Scripture and sacred writing both are nouns.

Word	Noun	Adjective	Verb	Adverb
Scripture	Yes	No	No	No
sacred writing	Yes	No	No	No

As nouns, sacred writing is a hypernym of Scripture; that is, sacred writing is a word with a broader meaning than Scripture:

Other hypernyms of Scripture include religious text, religious writing, sacred text.

Scripture (noun)	sacred writing (noun)
the sacred writings of the Christian religions	writing that is venerated for the worship of a deity