MITHRAS.  He was the god worshipped by the ancient Persians, and celebrated in their Mysteries as the symbol of the sun.  In the initiation in these Mysteries, the candidate passed through many terrible trials, and his courage and fortitude were exposed to the most rigorous tests.  Among others, after ascending the mystical ladder of seven steps, he passed through a scenic representation of Hades, or the infernal regions; out of this and the surrounding darkness he was admitted into the full light of Elysium, where he was obligated by an oath of secrecy, and invested by the Archimagus, or High Priest, with the secret instructions of the rite, among which was a knowledge of the Ineffable Name.

MOUNT CALVARY.  A small hill of Jerusalem, in a westerly direction, and not far from Mount Moriah.  In the legends of Freemasonry it is known as “a small hill near Mount Moriah,” and is referred to in the third degree.  This “small hill” having been determined as the burial-place of Jesus, the symbol has been Christianized by many modern masons.

There are many masonic traditions, principally borrowed from the Talmud, connected with Mount Calvary; such as, that it was the place where Adam was buried, &c.

MOUNT MORIAH.  The hill in Jerusalem on which the temple of Solomon was built.

MYRTLE.  The sacred plant in the Eleusinian Mysteries, and, as symbolic of a resurrection and immortality, the analogue of the acacia.

MYSTERIES.  A secret worship paid by the ancients to several of the pagan gods, to which none were admitted but those who had been solemnly initiated.  The object of instruction in these Mysteries was, to teach the unity of God and the immortality of the soul.  They were divided into Lesser and Greater Mysteries.  The former were merely preparatory.  In the latter the whole knowledge was communicated.  Speaking of the doctrine that was communicated to the initiates, Philo Judaeus says that “it is an incorruptible treasure, not like gold or silver, but more precious than everything beside; for it is the knowledge of the Great Cause, and of nature, and of that which is born of both.”  And his subsequent language shows that there was a confraternity existing among the initiates like that of the masonic institution; for he says, with his peculiar mysticism, “If you meet an initiate, besiege him with your prayers that he conceal from you no new mysteries that he may know; and rest not until you have obtained them.  For me, although I was initiated into the Great Mysteries by Moses, the friend of God, yet, having seen Jeremiah, I recognized him not only as an Initiate, but as a Hierophant; and I followed his school.”  So, too, the mason acknowledges every initiate as his brother, and is ever ready and anxious to receive all the light that can be bestowed on the Mysteries in which he has been indoctrinated.

MYSTES. (From the Greek [Greek:  my/o], to shut the eyes.) One who had been initiated into the Lesser Mysteries of paganism.  He was now blind, but when he was initiated into the Greater Mysteries he was called an Epopt, or one who saw.