In the _Upanishads_ the sacrifice of the horse is infused, as we have indicated, with mystic symbolism. We read: “The dawn in truth is the head of the sacrificial horse. The sun is the eye; the wind the breath ... the year the body, the heaven is the back ... the constellations the bones; the sky the muscles; the rivers, arteries and veins; the liver and spleen, the mountains; the herbs and trees, the various kinds of hair.” The horse is also identified with the sun: “The sun, as long as he rises is the fore part of the body; the sun, as long as he descends is the hind part of the body, &c.” The horse is also day and night in turn, and its birthplace is the sea; it carries the gods and the Asuras; it is the symbol of Death, “who is voracity”, from whom all things came. “There was not anything here before.” Death first “created this mind, desiring, _May I have a soul_. He went forth worshipping. From him, when worshipping, the waters were produced.... The froth of the waters which was there became consistent. This became the earth.... He made himself threefold. His eastern quarter is the head ... his western quarter is the tail, &c.”
The work of Creation proceeds, and then “he (Death as the Creator) resolved to devour all that he had created; for he eats all.... He is the eater of the whole universe; this whole universe is his food.”
After a year of purification the Creator slaughtered his horse body. “He gave up the animal to the gods. Therefore they (the gods) slaughter the purified animal, representing in its nature, as Prajápati, all deities. He (the Creator) is the Ashwameda[144] who shines.”
The gods performed the sacrifice to overcome the demons, the representatives of sin. Therefore the horse sacrifice removes all sin.
After much fantastic symbolism the following lesson in the form of a mantra is extracted from the parable of Creation:—
“From the unreal lead me to the real, from darkness lead me to light, from death lead me to immortality.”
The Upanishadic treatment of the Purusha myth differs somewhat from the Vedic, and is intended to strengthen the Monotheistic tendencies displayed in some of the hymns.
When the Universal soul, according to this later doctrine, took at the beginning “the shape of a man” ... he “beheld nothing but himself”.