Both Mithraism and Christianity became popular in Rome during the second century, A.D. As a Persian religion, Mithraism was far older and more venerable at the time, having been practiced as early as 1500, B.C. during the Aryan migration into both Persia and India. This was when the early Vedic god Mitra, similar to Mithra, began to be worshipped in India. During the sixth century, B.C., the Persian mystic Zarathustra (Zoroaster, as described in Greece) subordinated the story of Mithra to a grand epic struggle between a god (Ahura Mazda) and a devil (Ahriman) that supposedly culminates in judgment day, when all souls can expect to be consigned either to heaven or hell. Whether perceived as the primary god in his own right or subordinated to Ahura Mazda, Mithra was worshipped across Asia from the Indus River to the Black Sea when his religion finally arrived in Rome in a version that first emerged perhaps a hundred years before Christ.
Had Mithraism been accepted as the state religion of Rome, we would simply have replaced one set of silly ideas with another. Or would we? There are numerous parallels between Mithraism and Christianity:
- Both Mithras and Christ were portrayed as young and beardless; both sometimes appeared in the shepherd's role, and both saved mankind by performing sacrifical deeds.
- Both Mithras and Christ had virgin births in the sense that they were conceived without any sexual union between man and woman. Christ's father was said to be God, while Mithras was said to have had no father or mother, having emerged as an adult from a large rock.
- Both Mithraism and Christianity celebrated the birth of their god on the winter solstice, the 25th of December according to the Julian calendar. Both featured the sharing of presents, the use of Christmas trees with candles, and nativity scenes that included shepherds attracted by a sacred light. The special importance of this solstice ceremony to Mithraists would be indicated by the name Mithras, which derived from Meitras, which in Greek numerology refers to the number 365, the last day of the solar year at the winter solstice.
- Both the Old Testament and Mithraic legend told of the first human couple having been created. Mithra supposedly kept a watchful eye over their descendents until Ahriman caused a draught that caused such thirst that they begged Mithra for water.
- Both told of a major flood, in the case of Mithra through his having shot an arrow into a stone cliff to quench mankind's thirst. Unfortunately, the entire world's population was drowned in a flood produced by the water spout that gushed from the hole his arrow produced. One man alone (a Noah figure borrowed from the earlier Sumerian myth of Atrahasis) was warned in time and could therefore save himself and his cattle in an ark.
- Both Mithraism and Christianity emphasized mankind's redemption resulting from a sacrificial death followed by the god's ascent to heaven. In the case of Christ, it was the god himself (or his son) who was sacrificed; in the case of Mithra, it was a sacred steer that Mithra sacrificed.
- Both featured resurrection through sacrifice. Mithraism more obviously drew upon spring equinox fertility myths by depicting Mithra's sacrificial bull with a tail that consisted of sheaves of wheat that were supposedly scattered throughout the world once it was slaughtered. Also, the bull's blood formed the milky way, allowing human souls both to be born and to return to the heavens after death.
- Both told of a Last Supper linked with the blood sacrifice whose symbolic recreation by eating bread and wine provided salvation for all worshippers. After Mithra killed the bull depicted in Mithraic art, he feasted upon it with the Sun God and other companions before ascending to the heavens in the sun god's chariot. The sequence was slightly different in the New Testament: Christ's Last Supper necessarily preceded his crucifixion rather than following it, after which he ascended to heaven.
- Both emphasized purification through baptism, Mithraists by washing themselves in the blood of sacrificial oxen. While dying oxen bled to death on lattice floors built over their heads, initiates both drank and washed themselves with the blood that dripped on them.
- Both featured secret temples located underground. For Christians it was a temporary expedient to avoid persecution, but for Mithraists it became a permanent institution, each small chapel, called a Mithraeum, having seated no more than fifty worshippers and having been constructed to point from east to west. Rounded ceilings were painted blue and imbedded with gemstones. There were no windows except for a few chapels in which tiny holes in the ceiling that had been bored to let in the light of certain stars at particular times of the year.
- Both held Sunday to be sacred.
- Both encouraged asceticism. Mithraists were expected to resist sensuality and to abstain from eating certain foods.
- Both emphasized charity. Mithra was identified as the god of help who protected his worshippers, whatever their tribulations in life.
- Last and probably least, both emphasized a rock, Mithra having been born from one and the Vatican having been built on one.