The birth of the sun god Sol Invictus

25 December 274 CE, By order of the Roman Emperor Lucius Domitius Aurelianus, the birth of the sun god Sol Invictus was officially celebrated for the first time in Rome.

“Let us celebrate this day as a feast not for the sake of this sun, which is beheld by believers as much as by ourselves, but for the sake of him who created the sun" (Sermon of Augustine of Hippo)

Apollon-Sol depicted on a floor mosaic from the late 3rd century CE

He saw you when you were sleeping, he knew when you were awake. Until the last days of the Republic, Sol Indiges, the native Roman sun god, had been regarded as a being of lesser importance, was, with his radiate crown probably retrospectively, added to the cult of the divine Augustus and finally became the patron deity of the Roman emperors, after the discovery of the Pisonian conspiracy against Nero was attributed to the workings of Sol. He was “all-seeing” and thus knew of all outrages. Vespasian erected a huge statue in his honour around 75 CE and since the rule of the Nerva-Antonine dynasty, radiantly crowned Sol appeared on imperial coinage and as the western manifestation of Mithras as Sol Invictus Mithras. There was, however, an eastern form of the deities, of Mithras as well as Sol, competing with the Western Roman cult since mid-3rd century CE 
at the latest. The eastern cult’s centre, where the sun was revered under the name of Elagabalus, was based for centuries in the city of Emesa, present-day Homs in Syria. Emperor Septimus Severus married Julia Domna, daughter of an influential Elagabalus-priest, on the brink of the crisis of the 3rd century and her grand-nephew Varius Avitus Bassianus tried to give the Roman cult a certain Eastern colour according to his heritage and took his rule straight to the wall. He became one of the most vilified Roman emperors and his name a byword for decadence, Heliogabalus.

Bas-relief from the 4th century CE showing Mithras killing the bull in the Tauroctony turning his face to Sol Invictus

Nevertheless, it was during the rule of Bassianus that Sol Invictus was finally established as Imperial deity and when Emperor Aurelian had brought back Queen Zenobia’s rebellious Palmyrene Empire in Syria, of all the places, back into the folds of Rome, with his victory attributed to the western Sol Invictus, the deity was revered as supreme god of the Roman state cult. His birthday along with the anniversary of the dedication of his temple on the Campus Martius in Rome was ever since celebrated on December 25th, an old public holiday that reached back to the calendric date of the winter solstice of Caesar’s Julian calendar. At least since the early 4th century, Sol Invictus took on henotheistic features, he became the sole god that had absorbed the roles of many Greco-Roman deities, his cult, though, allowed for the existence and reverence of other divine beings, in contrast to monotheistic religions. Whether Sol and Mithras were merged into a single deity or remained individual gods remains unclear, but at least the army seems to have paid special regards to the mithraic aspect of Sol.

 A mosaic from the Vatican grottoes under St. Peter's Basilica, 
on the ceiling of the tomb of the Julii, 
representing Christ as the sun god Sol Invictus riding in his chariot. 
Dated to the 3rd century CE.

A hundred years later, when Christianity was declared to be the Roman state religion by Emperor Theodosius in 392, all other cults, including that of Sol Invictus, became illegal in the Empire. Several traits of the theology and the ritual acts of Sol Invictus had been integrated, though, voluntarily and involuntarily into Christianity and Pope Leo the Great still complained in the mid-450s about the custom of pilgrims bowing towards the sun before they entered St Peter’s and in Syria, Sol was revered at least until the 6th century. That Christ was born on December 25th as well might be a coincidence, but one that was at the very least tacitly accepted by the church fathers, while Sundays, as days of rest, were definitely Emperor Constantine’s idea of revering the sun: “On the venerable day of the Sun let the magistrates and people residing in cities rest, and let all workshops be closed. In the country however persons engaged in agriculture may freely and lawfully continue their pursuits because it often happens that another day is not suitable for grain-sowing or vine planting; lest by neglecting the proper moment for such operations the bounty of heaven should be lost.”

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