The Deeper Symbolism of Freemasonry from The Meaning of Masonry by Walter Leslie Wilmshurst.

“It is, of course, common knowledge that great secret systems of the Mysteries (referred to in, our lectures as ‘noble orders of architecture,’ i.e., of soul-building) existed in the East, in Chaldea, Assyria, Egypt, Greece, Italy, amongst the Hebrews, amongst Mahommedans and amongst Christians; even among uncivilized African races they are to be found. All the great teachers of humanity, Socrates, Plato, Pythagoras, Moses, Aristotle, Virgil, the author of the Homeric poems, and the great Greek tragedians, along with St. John, St. Paul and innumerable other great names—were initiates of the Sacred Mysteries.” [via]

Consider also:

  1. “Surely, then, it behoves us to acquaint ourselves with what that larger end consists, to enquire why the fulfilment of that purpose is worthy to be called a science, and to ascertain what are those ‘mysteries’ to which our doctrine promises we may ultimately attain if we apply ourselves assiduously enough to understanding what Masonry is capable of teaching us.”
  2. “For the moment let me merely say that behind all the official religion systems of the world, and behind all the great moral movements and developments in the history of humanity, have stood what St. Paul called the keepers or ‘stewards of the Mysteries.'”
  3. “We are told seven or more years was the normal period, though less sufficed in worthy cases. The most severe tests of discipline, of purity, of self-balance were required before a neophyte was permitted to pass forward, and a reminiscence of these tests of fitness is preserved in our own working by the conducting of the candidate to the two wardens, and submitting him to a merely formal trial of efficiency.”
  4. “The form of the teaching communicated has varied considerably from age to age; it has been expressed under different veils; but since the ultimate truth the Mysteries aim at teaching is always one and the same, there has always been taught, and can only be taught, one and the same doctrine.”
  5. “And by these finally he will discern how that there is a mystical ‘ladder of many rounds or staves,’ i.e., that there are innumerable paths or methods by means of which men are led upwards to the spiritual Light encircling us all, and in which we live and move and have our being, but that of the three principal methods, the greatest of these, the one that comprehends them all and brings us nearest heaven, is Love, in the full exercise of which God-like virtue a Mason reaches the summit of his profession; that summit being God Himself, whose name is Love.”