Lord Vishnu had so far taken nine avatars, and among those avatars, his first Matsya avatar is considered as an important avatar, since he has taken this avatar in order to protect a few holy persons from deluge, and the significance of this avatar is mentioned in Vedic texts, Puranas, bhagavatam and in the great epic Mahabharatha.
Once when Manu, who was the son of Lord Brahma, and also one of his first and foremost creation, was performing religious rituals on the banks of the Cherivi River, Andhra Pradesh. At that time a little fish asked for its protection.When Manu places the fish in the small bottle, it grows rapidly in size and again he put the fish into a tank,and then to the holy Ganges River, and finally to the ocean.
The great Matsya who was in the form of fish has advised Manu to carry with him the Rishis with sufficient food grains in a ship, on the day of the expected deluge (PRALAYAM). Manu ties the ship to the fish and then drove the ship to the Himalayas. The fish then reveals himself as Lord Vishnu and gives the power of creation to Manu.
There are very few temples dedicated to Lord Matsya, and among those temples, Sri Vedanarayana Temple also called as Matsya Narayana Temple is an ancient and a holy temple and it is situated at Nagalapuram town in Chittoor District, Andhra Pradesh. This temple is dedicated to Lord Vishnu, and he is worshipped in the form of Matsya (fish) avatar and he is mentioned as Matsya Narayana or Veda Narayana. There are only few temples dedicated to Matsya Avatar of Lord Vishnu, and amongst those temples, this temple is considered as a famous temple.
The temple is being properly maintained by Tirumala Tirupati Devasthanams, and as per their instructions, all the puja related activities are being performed at this temple in a well versed manner.
Surya Puja festival is being celebrated at this temple, once in a year, and during that time, sun rays would fall on Lord Matsya. According to legend, once the great Lord Varuna, the ocean god, had visited this temple, along with the holy River goddesses such as Ganga, Yamuna, Narmada and Godavari, and offered their worship to the great god, Sri Veda Narayana.
It is believed that worshipping Lord Matsya at this temple, would give good prospects in our life, and we would be able to live our life in a prosperous manner. Since Lord Matsya is the fish god, and dwells in the ocean, water related diseases like cold, cough, virus fever, diabetes would be relieved, and we would become healthier and wealthier in our life.