The First Man, the Mace of Mithra, and the Yellow-eared Dog
In the Pārsī Literature we find a story, unique of its kind, about the death of the first man, Gaya Marətan, and the birth of the yellow-eared dog: Aŋra Mainyu threw something on the navel of the Primal Man, but Ahura Mazdā transformed it into a dog and gave it life; thereafter the yellow-eared dog remains at the head of the Cinvatō bridge, watches the hellish souls, and is a loyal companion of Miθra (/ Mithra) who brandishes his mace three times every day, at the entrance of hell, upon the heads of the Daēva.
The Avesta Miθra, on his chariot, holds a vazra- ‘mace’ in his hand. The easily brandished vazra is the weapon par excellence of Miθra (like the vájra-, ‘thunderbolt’ of Indra) : it is with a hundred bosses, with a hundred blades, cast in (this) yellow metal, offensive, made of gold, the most offensive of weapons, the most defensive of weapons ; it is a beautiful mace well thrust down .
Miθra does not belong to the world of life; he is invisible, immaterial, and resides in the world of thought. However an astrological interpretation of the above story is tempting. There are two cosmic layers in this story: One, the death of the primal man, Gaya Marətan, and the genesis of the (shepherd) dog; the other, the kingship of Miθra over the celestial station, the place of the passing of the souls of the dead, where the celestial dog watches the Cinvatō Bridge. The Miθra figure seems more likely to be connected to Prajāpati-Orion, and then the dog would be Canis Major, the companion of Orion. In some Pārsī texts, the dog is clearly identified with the deity Rašnu. And finally, the (unique) Bull is Taurus.