The Keśin were long-haired ascetic wanderers with mystical powers described in the Rigveda (an ancient Indian sacred collection of Vedic Sanskrit hymns) Keśin Hymn (RV 10, 136). The Keśin ("long-haired one") are described as homeless, traveling with the wind, clad only in dust or yellow tatters, and being equally at home in the physical and the spiritual worlds. They are on friendly terms with the natural elements, the gods, enlightened beings, wild beasts, and all people. The Keśin Hymn also relates that the Keśin drink from the same magic cup as Rudra, which is poisonous to mortals.
The Keśin were unusual in the Rigveda for having an entire hymn dedicated to them—the only hymn in all the vedas that was dedicated to a group completely outside the Brahminical establishment. Interpretations of the Keśin Hymn (RV 10, 136) have varied widely over time, from viewing the Keśin as the Sun God (Surya), to seeing the Keśin as wild orgiastic imbibers of intoxicants, to a growing interpretation of the Keśin as ascetic mystics showing similarities to shamans and yogis.
The Rishis and the muni Keśin were two distinct types of religious seers in the Vedas. Unlike the Rishis, who took an active part in the Vedic community, the Keśin were described as muni, in its broader meaning of "to think, to muse, to contemplate, to meditate," along with the narrower meaning of being silent. The Rishi priests led prayers and worship as an integral part of the Vedic hierarchy and community. The Keśin were lone ascetics, living a life of renunciation and wandering mendicancy—they were shown as having spiritual power and authority that did not rely on the ritualistic worship and sacrifices of the Rishis. Some scholars see Buddha, whose names included Śākyamuni, as one who arose from the muni-Keśin tradition rather than the Rishi tradition.
The Keśin Hymn has a long history of evolving interpretation, including misleading or superficial translations of the word Keśin and of the meaning of the Keśin Hymn. Yāska (c. 500 BCE) interpreted Keśin to mean the sun or the sun God Surya. Sāyana (c. 14th century ACE) supported that view, followed by some early European Sanskrit scholars, including H. H. Wilson and M. Bloomfield. Hermann Oldenberg took the view that the Keśin Hymn described the "orgiastic practices of the old Vedic times" and the "drunken rapture" of the Keśin, which eventually evolved into the Buddhist goal of liberation.
The hymn shows the conception that by a life of sanctity the Muni can attain to the fellowship of the deities of the air, the Vayu, the Rudras, the Apsarases, and the Gandharvas; and, furnished like them with wonderful powers, can travel along with them on their course.
The Keśin Hymn (RV 10, 136)
He with the long loose locks supports Agni, and moisture, heaven, and earth:
He is all sky to look upon: he with long hair is called this light.
The Munis, girdled with the wind, wear garments soiled of yellow hue.
They, following the wind's swift course go where the Gods have gone before.
Transported with our Munihood we have pressed on into the winds:
You therefore, mortal men. behold our natural bodies and no more.
The Muni, made associate in the holy work of every God,
Looking upon all varied forms flies through the region of the air.
The Steed of Vāta, Vāyu's friend, the Muni, by the Gods impelled,
In both the oceans hath his home, in eastern and in western sea.
Treading the path of sylvan beasts, Gandharvas, and Apsarases,
He with long locks, who knows the wish, is a sweet most delightful friend
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