AVE , Hello, I'd like to offer you a Platonic interpretation of the Trier Relief. The Sun and Moon show a Platonic dualism, which is added to the zodiac.
The axis of the sun is in line with the axis of Mithras' arm and gaze, and also with the dog below. The axis of the Moon passes through the middle of Mithras' head. This axis passes slightly outside the gate of Cancer, the gate of descent catabasis (the gate of generation). This blue line is that of earthly reincarnation. The axis of the sun crosses the lunar axis on the torso of Mithras. He can therefore distribute souls either along the line of the moon, towards a return to the earth, or upwards, towards solar resurrection.
greetings