No, it isn't something from Harry Potter--it's much better, because it's real.
Mysterium Tremendum is a term that was coined in the early part of the 20th century to describe when someone has experienced the presense of the Holy, of the Wholly Other, of Divinity. Doubt, laugh or roll your eyes, but Aldous Huxley, certainly no Christian, described it this way:
"The literature of religious experience abounds in references to the pains and terrors overwhelming those who have come, too suddenly, face to face with some manifestation of the mysterium tremendum. In theological language, this fear is due to the in-compatibility between man's egotism and the divine purity, between man's self-aggravated separateness and the infinity of God."
I'm captivated by the profundity and implications of his description. I sort of look at it and ponder in awe. I hope you receive a similar high from it as well.