STO-118 – The Sacrifice of the Purusha (creation)
Vishnu, as soul of the entire cosmos, manifests innumerable universes from the pores of his skin and from his breathing. He then enters each universe, as the universal soul. From his navel springs a lotus flower, upon which is born Brahma. Brahma performs austerity and creates the world from sound beginning with the Gayatri mantra.
Before creating, Brahma wanting to perform yajna (sacrifice) since the universe is created and maintained only through sacrifice. As yet, though, he had no ingredients. Therefore, the Supreme Lord agreed to become the necessary ingredients. Through that symbolic sacrifice of the Lord, the first created being, all species were created, as well as human society, with its places of residence, its languages, etc. Brahma also created the various occupations and the corresponding system of four varnas Thus the brahmins represent his head of the Supreme Lord; the kshatriya are his arms, the vaishyas his thighs and the shudras his legs.
Note: One should be careful of considering this story a mere myth (in the sense of a fictitious story) It relates to a sophisticated theology of microcosm-macrocosm. For example, the four varnas are considered not just a human construct, but an ontological reality, represented through various archetypes – the priest, the teacher, the warrior, the businessman, the artisan, and so on. They appear in all societies irrespective of religious or secular belief.