Deus absconditus refers to the Christian theological concept of the fundamental unknowability of the essence of God. The term is derived from the Old Testament of the Christian Bible, specifically from the Book of Isaiah: "Truly, you are a God who hides himself, O God of Israel, the Savior". Quotes from the English and Greek Bible referring to the hidden God are listed in "Deus Absconditus - The Hidden God" by M.M Nikoletseas pp 21-27