"The mysteries of Dionysos-Sabazius had been replaced by the rites of Mithras, whose 'caves' superseded the crypts of the former god, from Babylon to Britain."
     - M. P. Blavatsky, Isis Unveiled

"...The later Hellenistic period is one of pessimism, a world where the bankruptcy of both the rationalism of the Greeks and the ancient institutionalized authoritarian religions of the Orient is manifest. And the way out of the dilemma for both is a savior who is above reason and who abolishes the law."
     - Richard N. Frye, The Heritage of Persia

An Iranian Angel of Light?
"Among the most universal cults of the ancient Armenians was that of Mithra, who was identified on the one hand with the sun, or Helios, on the other, with Apollo and Hermes. Mithra was originally conceived of as a kind of angel, a power of light who fights on the side of Ahura-Mazda. This warlike characteristic he seems always to have retained.... Mithra's festival, the Mithrakana, was celebrated in Iranian lands on the sixteenth day of the seventh month, and survived in modified form right up to Muslim times."
     - Burney and Lang, The Peoples of the Hills

"At the end of the nineteenth century Franz Cumont, the great Belgian historian of ancient religion, published a magisterial two-volume work on the Mithraic mysteries based on the assumption of the Iranian origins of the cult. Cumont's work immediately became accepted as the definitive study of the cult, and remained virtually unchallenged for over seventy years." 
     - David Ulansey, "The Cosmic Mysteries of Mithras"

Scholars believed that the cult of Mithras was derived from the ancient Aryan worship of Ahura-Mazda. "Dating from around the 15th century BC, Mithraism emerged in ancient Persia. 'Mihr' (the Persian form of Mithras) was the word not only for the Sun but also for a friend; and that seems to be how this pagan god was originally worshipped - as both supreme sun god and god of love....By the beginning of the third century BC, the militaristic rulers in western outposts of what had been the Persian empire were venerating Mithras as a divine warrior, no longer a loving Sun god but the unconquerable god of soldiers and friend of power."
     - Quest for the Past

"Mithra was believed to be the eye of Ahura Mazda and to rule over the earth. In the imagination of the Mithraic cult he came to replace the supreme deity. He engaged in a great struggle between good and evil in which he was steadily victorious. To assure his victory, he sacrificed a great bull which was the prototype of the living world of nature. Through this sacrifice nature was made fertile."
     - Ninian Smart, The Religious Experience of Mankind

Called by the Zoroastrians Zeruana-Akarene, his glory "is too exalted, his light too resplendent for either human intellect or mortal eyes to grasp and see. His primal emanation is eternal light which, from having been previously concealed in darkness, was called out to manifest itself, and thus was formed Ormazd, 'the King of Life'. He is the first-born of boundless time, but like his own antitype, or preexisting spiritual idea, has lived within primitive darkness from all eternity. His Logos created the pure intellectual world in six periods. The six Amshaspands, or primitive spiritual men, whom Ormazd created in his own image, are the mediators between this world and himself. Mithras is an emanation of the Logos and the chief of the twenty-eight izeds, who are the tutelary angels over the spiritual portion of mankind - the souls of men. The Ferouers are infinite in number. They are the ideas or rather the ideal conceptions of things which formed themselves in the mind of Ormazd or Ahuramazda before he willed them to assume a concrete form. They are what Aristotle terms 'privations' of forms and substances."
     - M. P. Blavatsky, Isis Unveiled

Alternative Theories of Origin
"It is probable...that the western Mithras had its roots in a daevic cult of the god as practiced in Mesopotamia and Anatolia, and not in the cult of the Zoroastrianized Mithra in Iran. The western Mithras is a savior god in an era of savior gods."
     - Richard N. Frye, The Heritage of Persia

"A central feature of the ceremonial associated with Mithras was the taurobolium, the ritual slaughter of a bull which commemorated and repeated Mithras' primeval act. The initiate was baptized in its blood, partaking of its life-giving properties. It may be noted that this part of the ceremonial closely resembled the ritual of the cult of Cybele, the Great Mother of Asia Minor, which had been brought to Rome three centuries before Christ.."
     - Ninian Smart, The Religious Experience of Mankind

"...By far the most important icon in the Roman cult was the tauroctony. This scene shows Mithras in the act of killing a bull, accompanied by a dog, a snake, a raven, and a scorpion; the scene is depicted as taking place inside a cave like the Mithraeum itself. This icon was located in the most important place in every mithraeum, and therefore must have been an expression of the central myth of the Roman cult."
     - David Ulansey, "The Cosmic Mysteries of Mithras"

There is no Iranian myth, however, of Mithra killing a bull. This calls into question the traditional explanation that the tauroctony is a pictorial representation of an Iranian myth. Mithraism may have had an entirely different origin and the name of Mithra/Mithras may have been borrowed to help legitimize and popularize the religion. At the First International Congress of Mithraic Studies , held in Manchester England in 1971, several scholars came up with a radical new theory - that the tauroctony was actually a star map. 

"This remarkable explanation of the tauroctony is based on two facts. First, every figure found in the standard tauroctony has a parallel among a group of constellations located along a continuous band in the sky: the bull is paralleled by Taurus, the dog by Canis Minor, the snake by Hydra, the raven by Corvus, and the scorpion by Scorpio. Second, Mithraic iconography in general is pervaded by explicit astronomical imagery: the zodiac, planets, sun, moon, and stars are often portrayed in Mithraic art; in addition, numerous ancient authors speak about astronomical subjects in connection with Mithraism. In the writings of the Neoplatonic philosopher Porphyry, for example, we find recorded a tradition that the cave which is depicted in the tauroctony and which the underground Mithraic temples were designed to imitate was intended to be 'an image of the cosmos.'"
     - David Ulansey, "The Cosmic Mysteries of Mithras"

In 128 B.C.E, the noted Greek astronomer Hipparchus discovered the precession of the equinoxes - a wobble in the axis of the earth's rotation which causes the celestial equator to intersect a new constellation of the Zodiac every 2,160 years. 

"During...the 'Age of Taurus,' lasting from around 4,000 to 2,000 B.C., the celestial equator passed through Taurus the Bull (the spring equinox of that epoch), Canis Minor the Dog, Hydra the Snake, Corvus the Raven, and Scorpio the Scorpion (the autumn equinox): that is, precisely the constellations represented in the Mithraic tauroctony."
     - David Ulansey, "The Cosmic Mysteries of Mithras"

As the intersection of the celestial equator during the spring equinox moved to the constellation of Aires, the Age of Taurus came to an end - an event symbolized as the death of a bull.

"This, I propose, is the origin and nature of Mithras the cosmic bull-slayer. His killing of the bull symbolizes his supreme power: namely, the power to move the entire universe, which he had demonstrated by shifting the cosmic sphere in such a way that the spring equinox had moved out of Taurus the Bull."
     - David Ulansey, "The Cosmic Mysteries of Mithras"

"The cult of Mithras had been taken up with great enthusiasm by the Roman legions and had traveled with them from Iran to Rome, to Tunis, to the Rhine and even on to London and Hadrian's Wall. Mithras' cult satisfied many of the same urges that would also attract people to Christianity. It was a brotherhood where rank and mutual obligation were based not upon accepted social codes but on the secret bonds of a closed circle, an underground network of close allegiances operating right across the strong social fabric of the Empire."
     - John Romer, Testament

In the Gospel of Mark, "we find Jesus, at the moment of his baptism, having a vision of 'the heavens torn open.' Just as Mithras is revealed as a being from beyond the universe capable of altering the cosmic spheres, so here we find Jesus linked with a rupture of the heavens, an opening into the numinous realms beyond the furthest cosmic boundaries. "
     - David Ulansey, "The Cosmic Mysteries of Mithras"

The Mithraeum
The mysteries of Mithra were celebrated in underground temples, built in imitation of caves, called methraei.

"The typical mithraeum was a small rectangular subterranean chamber, on the order of 75 feet by 30 feet with a vaulted ceiling. An aisle usually ran lengthwise down the center of the temple, with a stone bench on either side two or three feet high on which the cult's members would recline during their meetings. On average a mithraeum could hold perhaps twenty to thirty people at a time....There were many hundreds-- perhaps thousands-- of Mithraic temples in the Roman empire." 
     - David Ulansey, "The Cosmic Mysteries of Mithras"

"After killing the bull, Mithra and Sol seal their friendship by a banquet in which they share the flesh of the bull. The two gods are served by persons wearing animal masks. Having finished their meal, the two gods ascend to heaven riding in Sol's chariot. This banquet constitutes the paradigm for the communal meal shared by the followers of the god, who likewise war masks that indicate their degrees of initiation. In the myth, the life of the cosmos is renewed by the blood of the bull. In a similar fashion, the followers of Mithra believed that by eating the meat of a bull and drinking its blood they would be reborn to ascend with Mithra to the celestial home of the Sun, and immortality."
     - An Encyclopedia of Archetypal Symbolism

The Seven Degrees
"Unlike the other mystery religions, Mithraism was open only to men, so that in no sense could it be regarded as a universal faith. Mithras, the unconquered and unconquerable sun (sol invictus), symbolized the courage, success, and confidence of the soldier. The ethics of the cult demanded self-control and other virtues necessary to a legionary, and this was one main reason for its spread through the army. Imperial patronage helped too. From the second century A.D. Roman Emperors assumed the title Invictus."
     - Ninian Smart, The Religious Experience of Mankind

"Mithraism recognized seven degrees of divine knowledge. Members could advance from one degree to the next by undergoing a special initiation, tests of courage and stamina, at each stage. The seven ranks corresponded to the seven known celestial planets, and scaling them was a metaphor for the passage of the soul through the planetary spheres toward heaven."
     - Ancient Wisdom and Secret Sects

"The lowest degree of initiation was known as the Sacrament...and it symbolized, according to present-day Mithraists, the death of the new member, from which he would arise reborn as a new man." 
     - Arkon Daraul, Secret Societies

"...In the text which is known under the title of the Liturgy of Mithra, but which is pervaded with Hermetic Gnosticism, we read: 'Today, having been born again by thee, out of so many myriads rendered immortal..' or 'Born again for rebirth of that life-giving birth...' 
     - Mircea Eliade, Rites and Symbols of Initiation

"Ascension was symbolized by seven grades of initiation, each stage governed by a 'plant': Raven (Mercury); Bride (Venus); Soldier (Mars); Lion (Jupiter); Persian (the moon); Courier of the Sun (the sun); and Father (Saturn). The ultimate goal was to transcend all levels of the cosmos and to attain the level of the fixed stars, or aeternitas."
     - An Encyclopedia of Archetypal Symbolism

"...Each grade had a distinctive mask or dress to be worn at rites celebrated secretly in caves." 
"According to some students of the subject... converts could be accepted into the 'church' only by undergoing 12 trials, including ordeals by fire, water, hunger, cold, flagellation, bloodletting, and branding. The whole exhausting program lasted from two to seven weeks. Successful candidates swore to keep the rites secret. Then they were baptized."
     - Quest for the Past

Magic and Visions
"This very ancient cult, from which more than one present-day secret society may well be derived, is thus seen to contain many of the elements which underlie organizations of this sort. It is a training system; it attempts to produce in its members a real or imagined experience of contact with some supreme power. The magical element is there, too, shown in the belief in the power of certain names to achieve things which cannot be done by men."
"...The secret of religion was partly that the worshipper must restrain himself physically in order to attain power over himself and over others. This graphic teaching of the diversion of sexual power into psychic channels shows that the Mithraists followed in essence the pattern of all mystical schools which believed in the production of power through discipline. In this they are clearly distinguished from the more primitive and less important orgiastic schools, which merely practiced indiscriminate indulgence, mass immorality, and so on."
     - Arkon Daraul, Secret Societies

The Mithra Liturgy "gives instructions on how to achieve visions, descriptions of visions, and culminates with the visionary becoming a spirit possessed oracle."
     - Stevan Davies (Mediators) 

"After you have said these things, he will immediately respond with a revelation. Now you will grow weak in soul and will not be in yourself, when he answers you....And even if you are alone, and you undertake the things communicated by the god, you speak as if prophesying in ecstasy."
     - Mithra Liturgy, (H. D. Betz The Greek Magical Papyri in Translation (transl. Marvin Meyer)

Hyperlinks

• Egyptian and Pagan Themes in Christian Tradition
• Isis, the Black Virgin
• Mani, the Ambassador of Light