As per Hindu legend, Somukasura a demon, defeated Brahma, the Hindu god of creation and stole the four Vedas (sacred texts) from him. Brahma was helpless and he did severe penance in the banks of Tamiraparani River seeking favour from Vishnu in the form of Vaikuntanathan. Pleased by the penance, Vishnu appeared to Brahma and promised to retrieved the Vedas. Taking form of a celestial 'Matsya' Lord Vishnu killed the demon Somuka and restored the Vedas to Brahma. He also wished to set his abode as Srivakuntam and resided there as Vaikuntanatha.