Throughout her life, Hildegard had experienced visions, beginning at the age of 3. (Oliver Sacks attributed these to migraines). At age 42, she had a powerful experience that radically changed her life. She described this moment in her writings:

And it came to pass … when I was 42 years and 7 months old, that the heavens were opened and a blinding light of exceptional brilliance flowed through my entire brain. And so it kindled my whole heart and breast like a flame, not burning but warming… and suddenly I understood of the meaning of expositions of the books…

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