Namuchi! The Asura Namuchi, from fear of Vasava,
had entered a ray of the Sun. Indra then made friends with Namuchi and
entered into a covenant with him, saying, 'O foremost of Asuras, I shall
not slay thee, O friend, with anything that is wet or with anything that
is dry! I shall not slay thee in the night or in the day! I swear this to
thee by truth.' Having made this covenant, the lord Indra one day beheld a
fog. He then, O king, cut off Namuchi's head, using the foam of water (as
his weapon). The severed head of Namuchi thereupon pursued Indra from
behind, saying unto him from a near point these words, 'O slayer of a
friend, O wretch!' Urged on incessantly by that head, Indra repaired to
the Grandsire and informed him, in grief, of what had occurred. The
Supreme Lord of the universe said unto him, 'Performing a sacrifice,
bathe with due rites, O chief of the celestials, in Aruna, that tirtha
which saveth from the fear of sin! The water of that river, O Shakra,
hath been made sacred by the Munis! Formerly the presence of that river
at its site was concealed. The divine Sarasvati repaired to the Aruna,
and flooded it with her waters. This confluence of Sarasvati and Aruna is
highly sacred! Thither, O chief of the celestials, perform a sacrifice!
Give away gifts in profusion! Performing thy ablutions there, thou shall
be freed from thy sin.' Thus addressed, Shakra, at these words of Brahma,
O Janamejaya, performed in that abode of Sarasvati diverse sacrifices.
Giving away many gifts and bathing in that tirtha, he of a hundred
sacrifices, the piercer of Vala, duly performed certain sacrifices and
then plunged in the Aruna. He became freed from the sin arising out of
the slaughter of a Brahmana. The lord of heaven then returned to heaven
with a joyful heart. The head of Namuchi also fell into that stream, O
Bharata, and the Asura obtained many eternal regions, O best of kings,
that granted every wish."

Vaishampayana continued, "The high-souled Baladeva having bathed in that
tirtha and given away many kinds of gifts, obtained great merit. Of
righteous deeds, he then proceeded to the great tirtha of Soma. There, in
days of yore, Soma himself, O king of kings, had performed the Rajasuya
sacrifice. The high-souled Atri, that foremost of Brahmanas, gifted with
great intelligence became the Hotri in that grand sacrifice. Upon the
conclusion of that sacrifice, a great battle took place between the gods
(on the one side) and th