I am answering the question “are Hildegard of Bingens visions…

I am answering the question “are Hildegard of Bingens visions really from God” for a college class. I’m going through her writings to test it all against scripture. Deuteronomy 18: 22 says “when a prophet speaks in the name of the Lord, if the thing does not happen or come to pass, that is the thing which the Lord has not spoken; the prophet has spoken presumptuously; you shall not be afraid of him”. My question is, how are we to determine if it did not come true or just has not happened yet? Also with what amount of scrutiny are we to test what they say against scripture? For example, in one place Hildegard says “after the birth of anti christ, heretics will preach their doctrines undisturbed, resulting in Christians having doubts against their Holy Catholic faith”. The Catholic religion, and what they practice is not truly biblical, therefor would that make this prophecy unbiblical?