Iconography
Much about the cult of Mithras is only known from reliefs and sculptures. There have been many attempts to interpret this material.
Mithras-worship in the Roman Empire was characterized by images of the god slaughtering a bull. Other images of Mithras are found in the Roman temples, for instance Mithras banqueting with Sol, and depictions of the birth of Mithras from a rock. But the image of bull-slaying (tauroctony) is always in the central niche. Textual sources for a reconstruction of the theology behind this iconography are very rare. (See section Interpretations of the bull-slaying scene below.)
The practice of depicting the god slaying a bull seems to be specific to Roman Mithraism. According to David Ulansey, this is "perhaps the most important example" of evident difference between Iranian and Roman traditions: "... there is no evidence that the Iranian god Mithra ever had anything to do with killing a bull."
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