The Seven Grades of Mithraism: A Syllabus With No Textbook

In a small room at Ostia, the port town below Rome, there is a mosaic floor. It runs the length of the aisle between two dining benches, from the door to the altar, and it is divided into seven panels.

Each panel holds a handful of symbols. A raven and a small cup. A lamp and a diadem. A kit bag, a lance, a helmet. A fire-shovel, a rattle, a thunderbolt. A curved blade and a crescent moon. A torch and a radiate crown. A staff, a sickle, a Phrygian cap.

To reach the image of the god at the far end, you walked over all seven in order. The floor of the Felicissimus mithraeum is the clearest surviving statement of what Mithraism was structurally: not a congregation, but a ladder.

The rungs, and who owned them

The sequence, lowest to highest, with the planet attached to each:

• Corax, the Raven: Mercury
• Nymphus, the Bridegroom: Venus
• Miles, the Soldier: Mars
• Leo, the Lion: Jupiter
• Perses, the Persian: the Moon
• Heliodromus, the Sun-Runner: the Sun
• Pater, the Father: Saturn

This is not reconstruction. Three independent kinds of evidence agree. The Ostia mosaic gives the order and the symbols. Painted inscriptions at Santa Prisca in Rome, excavated in the 1950s and published by Vermaseren and van Essen, address members by grade in a repeated formula: hail to the Lions, whose guardian is Jupiter. And Jerome, a Christian writer with no reason to get it right or wrong, simply lists the seven names in a letter.

When a mosaic floor in a port town, painted plaster in Rome, and a churchman's correspondence all produce the same seven words in the same order, the ladder is about as well attested as anything in the mystery cults gets.

The word that shouldn't exist

Second from the bottom sits a problem.

Nympha is ordinary Latin for a bride. Nymphus is not a word. Latin does not form a masculine of it, there is no other context in the language where it appears, and any Roman reading it would have registered it as wrong, roughly the effect of writing "bridegroom" as "bridess".

Someone invented it, on purpose, for this rank. A man at the second grade was a male bride. Whose, to what, and why the cult wanted a deliberate grammatical impossibility in the middle of its hierarchy, nobody says.

The symbols for that grade at Ostia are a lamp and a diadem, which reads like a wedding. That is as far as the evidence goes. Everything past it is guesswork, and there has been a great deal of guesswork.

A ladder that is also a sky

The planetary pairings are where the grades stop looking like ranks and start looking like a route.

Roger Beck's reading, the most influential of the last few decades, takes them as exactly that: the mithraeum was built as a model of the cosmos, and climbing the grades enacted a soul's ascent through the planetary spheres. Porphyry, writing in the third century and the closest thing the cult has to a friendly outside witness, says plainly that the cave was designed as an image of the universe and discusses gates through which souls pass.

There is a further piece of evidence, and it comes with a warning attached. Origen, arguing against the pagan philosopher Celsus, reports that the Mithraists used a ladder with seven gates, each of a different metal, each assigned to a planet.

It fits beautifully. It is also a Christian quoting a pagan critic, neither of them initiates, at two removes from the thing described. And the planetary order Celsus gives does not match the order the grades actually use. That mismatch is unresolved. Take the ladder as suggestive rather than settled.

What a promotion ladder implies

Here is the thing the grades tell us that the pictures cannot.

You cannot run a seven-stage hierarchy without content. Somebody had to decide when a Raven was ready to become a Bridegroom. There was a threshold, a test, a thing learned or endured or demonstrated. Multiply that by six transitions, by the roughly four hundred mithraea known or suspected across the empire, across three centuries, and the volume of teaching that once existed was enormous.

Not one sentence of it survives. Not a rule, not a catechism, not a promotion criterion, not a complaint about an unfair Father. The most organised mystery cult in the Roman world left a floor plan of its curriculum and nothing whatsoever of the curriculum.

The grades also puncture a comfortable assumption. Dedications suggest most men never climbed far, and a given mithraeum had very few Patres, often exactly one. Seating for thirty, one Father, and six rungs between him and the newest Raven. Whatever else it was, it was a competitive institution, and most people in it stayed near the bottom.

Reading a hierarchy with the words removed

What we are left with is a shape. Seven names, one of them coined for the purpose. Seven planets in an order that does not quite agree with our one outside description. A room built to seat few, with a ceiling that meant something, and a picture at the end of it that we still cannot read.

It is a curious kind of evidence: the organisational chart of a belief system, complete and detailed, attached to no beliefs. We know exactly how a man moved through the cult of Mithras and nothing at all about what moved in him.