Mbh 1.71.7a

“My father Kanwa, in answer to that Rishi’s enquiries, said, ‘Viswamitra, of old, having been engaged in the austerest penances alarmed Indra, the chief of the celestials, who thought that the mighty ascetic of blazing energy would, by his penances, hurl him down from his high seat in heaven.’ Indra, thus alarmed, summoned Menaka and told her, ‘Thou, O Menaka, art the first of celestial Apsaras. Therefore, O amiable one, do me this service. Hear what I say. This great ascetic Viswamitra like unto the Sun in splendour, is engaged in the most severe of penances. My heart is trembling with fear. Indeed, O slender-waisted Menaka, this is thy business. Thou must see that Viswamitra of soul rapt in contemplation and engaged in the austerest penances, who might hurl me down from my seat. Go and tempt him and frustrating his continued austerities accomplish my good. Win him away from his penances, O beautiful one, by tempting him with thy beauty, youth, agreeableness, arts, smiles and speech.’ Hearing all this, Menaka replied, ‘The illustrious Viswamitra is endued with great energy and is a mighty ascetic. He is very short-tempered too, as is known to thee. The energy, penances, and wrath of the high-souled one have made even thee anxious. Why should I not also be anxious? He it was who made even the illustrious Vasishtha bear the pangs of witnessing the premature death of his children. He it was who, though at first born as Kshatriya, subsequently became a Brahmana by virtue of his ascetic penances. He it was who, for purposes of his ablutions, created a deep river that can with difficulty be forded, and which sacred stream is known by the name of the Kausiki. It was Viswamitra whose wife, in a season of distress, was maintained by the royal sage Matanga (Trisanku) who was then living under a father’s curse as a hunter. It was Viswamitra who, on returning after the famine was over, changed the name of the stream having his asylum from Kausik into Para.