According to the first three verses of the book of Revelation, God delivered an 'unveiling" of concealed things to his Son Yeshua. He, in turn, revealed it to his angel who revealed it to John to reveal to Yeshua's bondservants. Apocalypse of Messiah, the first teaching in the series on the book of Revelation, introduces us to the apocalyptic genre of literature in order to provide context for the book.
The mystic, the man of faith, does not want to just learn about God and study about God but to actually be swept up with the unseen, caught up into the divine, whether in the body or out of the body, I do not know, but to know God rather than just to know about God. The book of Revelation offers us that opportunity.