The Upanishads - Mandhata Global

From Him thus fatigued and heated, His fame and
vigour departed. The pranas (organs) are verily fame
and vigour. When the pranas went out His body began
to swell, but the mind was set on the body.
He desired: "Let this body of Mine be fit for a sacrifice
and let Me be embodied through this." Thinking thus,
He entered the body. Because the body swelled (asvat),
therefore it came to be called horse (asva). And because
it became fit for sacrifice (medhya), therefore the Horsesacrifice
came to be known as Asvamedha. He who
knows this verily knows the Horse- sacrifice. Prajapati,
desiring again to sacrifice with the great sacrifice,
imagined Himself as the horse and letting the horse
remain free, He reflected on it. At the end of a year he
sacrificed it to Himself and dispatched the other animals
to the gods. Therefore priests even now sacrifice to
Prajapati the sanctified horse dedicated to all the gods.
Verily, the sun who shines yonder is the Horse-sacrifice.
His body is the year. This earthly fire is the arka
(sacrificial fire), whose limbs are these worlds. So these
two, fire and the sun, are the arka and the Asvamedha
(Horse-sacrifice). These two, again, become the same
god, Death. He who knows this conquers further death;
death cannot overcome him; death becomes his self; and
he becomes one with these deities.
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