mysteriousness

noun

1. (uncountable, usually)The quality of being mysterious.

   “1651, Jeremy Taylor, Twenty-Seven Sermons for the Summer Half-Year, Sermon II, Part II in ΕΝΙΑΥΤΟΣ: A Course of Sermons for All the Sundays of the Year, London: Tyler & Royston, 1668, p. 14, https://books.google.ca/books?id=heNBAQAAMAAJ&printsec=frontcover#v=onepage&q&f=false This may seem strange; and indeed it is so: and it is one of the great mysteriousnesses of the Gospel.”

   “This sort of mysteriousness, which is always so becoming in a hero, threw a fresh grace in Catherine's imagination around his person and manners, and increased her anxiety to know more of him.”

   “His children had urged him to travel: Mary Chivers had felt sure it would do him good to go abroad and "see the galleries." The very mysteriousness of such a cure made her the more confident of its efficacy.”

   “And all this is not changed by adding "mysterious" experiences to "manifest" ones, self-confident in the wisdom that recognizes a secret compartment in things, reserved for the initiated, and holds the key, O mysteriousness without mystery, O piling up of information! It, it, it!”