Mithras was the focus of a Roman mystery-cult and, as a result, both his mythological story and the nature of his worship are hard to pinpoint in the evidence. While the worship of the god, in various forms, preceded the Romans, historians consider the mystery-cult that is most associated with him today as being a uniquely Roman one. As the historian Carly Silver astutely notes (2010):

Roman Mithras was a distant relative, not a direct descendant, of Indo-Iranian gods

Sanctuaries dedicated to his worship – today know as Mithraea, singular: Mithraeum – and the elusive initiations involved, were geographically widespread throughout the Roman empire, and as a result are quite prominent in the archaeological landscape. This prominence of a mystery-cult, seemingly growing in popularity during the first and second century AD, has attracted many to compare it with a similar contemporary religious movement spreading through the empire at that time – the various sects of Christianity.

Many ancient myths share common threads, common themes, common storylines, and indeed common means of telling those stories, so it is perhaps of little surprise to see thematic crossovers between stories of Mithras and stories of Jesus. But the alleged strong similarities in their birth stories needs examining. It is commonly claimed today that Mithras was born of a virgin on the 25th of December, but our ancient sources do not offer any real support for this.

Birthday story

The easiest element to clarify first is the story of Mithras’ birth. It is regularly claimed in the modern day that Mithras was born of a woman, and one of virginal status. The origins of this claim are hard to pin down in the modern popular histories, but it seems to derive, possibly, from a late Armenian tradition. The ancient tradition for Mithras’ birth is actually one of the few areas we can be relatively clear about (Commodian [third century AD], Instructiones1.13):

The unconquered one [Invictus Mithras] was born from a rock, if he is regarded as a god.

According to myth, Mithras was born from a rock, not a human. The image of his birth, which exists as a common artistic subject, often portrays him coming out of the rock with a knife in his hand. He is naked, as one would expect at birth, but he is not a baby – he is most often shown to be a youth.

Interestingly, for the topic at hand, early Christians knew of this mythical tradition and did in fact consider the story to have been stolen from Christian scripture, but it was not the birth of Christ. The second-century writer Justin Martyr wrote (Dialogue with Trypho 70):

And when those who record the mysteries of Mithras say that he was begotten of a rock, and call the place where those who believe in him are initiated a cave, do I not perceive here that the utterance of Daniel, that a stone without hands was cut out of a great mountain, has been imitated by them, and that they have attempted likewise to imitate the whole of Isaiah’s words?

This story offers no real parallel to the story of Jesus Christ, born a baby, of a mortal virgin, in a stable. Interestingly, the scholar David Ulansey has argued that a closer parallel can be found in the birth story of the Greek hero Perseus, although his interpretation is not universally accepted (1989, pp. 35-36). This was actually a parallel that concerned Justin Martyr, who mentions Perseus’ virginal birth from Danae and describes it’s origin colourfully as “the deceiving serpent counterfeited also this.” That is to say, the Devil invented this Perseus myth before the coming of Christ to create doubt in the minds of mankind.

To that end, the virginal story of Mithras is a later creation and bears no relation to the cult of Mithras during the Roman Imperial period.

Birthdate

The birthdate question is slightly harder to investigate. The reason why it is so hard is because no ancient source actually gives a supposed date for Mithras’ birth. In fact, there is no ancient source that mentions a festival celebrating the day of his birth at all. This historical problem is compounded by the fact that the cult of Mithras never received state funding or support, meaning that its festival dates do not appear on any surviving Roman calendars. So where does this claim that his birthdate was the 25th of December come from?

Franz Cumont, the founder of Mithraic Studies, speculated that the 25th of December may have been a feast-day for followers of Mithras (1910, p. 167). This proposal was based almost exclusively on the fact that the December 25th was a sacred day for the sun god Sol. Coming only a few days after the winter solstice, the birth of Sol (the waxing of the sun) was a day of celebration and appears in a mid-4th century AD calendar. However, Cumont was not overly bold in his assertion, and warned his readers that (1910, pp. 167-168):

As generally with everything concerned with the heortology (study of festivals) of the Mysteries, our ignorance is absolute.

But the claim is older than Cumont, it actually appears in Medieval Christian writing. An unknown scholiast to the work of Dionysius Bar-Salibi wrote (translation from Ramsay MacMullen 1997, p. 155):

It was in fact customary among the pagans to celebrate the festival of the Sun’s birth on 25th December […] But when the teachers of the Church realised that Christians were allowing themselves to take part, they decided to observe the Feast of the true Birth on the same day.

But what has this got to do with Mithras? As Roger Beck notes, the only evidence that does exist for a festival on the 25th December is the one dedicated to the Sun-god Sol Invictus (1987, p. 299 n.2). The festival does not appear on any Roman festival calendars until the mid-fourth century AD, which corresponds with the patronage offered to the god by the emperor Aurelian, who in AD 274 built a temple to Sol Invictus. However, to connect this late festival with Mithras requires some historical gymnastics.

First: “Invictus” is an epithet often attributed to Mithras on inscriptions. Hence Commodian was able to refer to him as Invictus, knowing that name would be self explanatory. Having said that, Invictus was a very popular epithet for many gods, and indeed it was also used by emperors as well. So its attribution to Mithras is not unique.

Second: Sol and Mithras were often syncretised in worship, to the point where some dedications refer to the god as Sol Invictus Mithras. However, the two gods were considered separate, and often appear together in contemporary paintings. Mithras was also conflated with other gods as well, such as Phanes. Third: Mithras is often associated with the sun, or at least light, so a celebration of or around the winter solstice makes sense on paper. This is true, but it is perhaps a stretch of the evidence to say he was worshipped as the sun-god.

Until further evidence comes to light, it must be assumed that the festival of the 25th December, implemented in the late third century, was for the sun-god Sol. Any link to Mithras may seem to make logical sense, based on extrapolation, but there is no direct evidence to support it. The subject of the designation of Christmas Day to the 25th of December is to be dealt with in a different post.

The story of Mithras’ virginal birth bears no relation to the birth story of Jesus Christ, it is false. The lack of any direct evidence for the festivals dedicated to Mithras, allied with the fact that any mention of December 25th as a Roman festival date assigns it to a different god, Sol, suggests that this part of the theory is also not based on solid research. Even if it is believed that Mithraists celebrated his birthday on the 25th December, this does not prove that his was the inspiration for the Christian festival date. But, because many scholars agree that followers of Mithras may have celebrated on the 25th of December, it cannot be ruled out as completely false.

For this reason we have rated this claim mostly false.