The Matsya Avatar is the first incarnations of Lord Vishnu. The Matsya avatar never made into a independent status for worship. It has no temples.
Once when Lord Brahma, was about to fall asleep, at the end of the Kalpa (one day of Brahma - equal to 4320 million year), a cunning demon named Hayagriva had been hanging around, took the advantage to steal from Lord Brahma, the Vedas. But Lord Vishnu caught the asura , in this act, and to retrieve the Vedas. Lord Vishnu noticed King Satyavrata, who was doing the rituals of offerring water to God. Immediately Lord Vishnu took the form of a fish (Matsya), descended into water. When Stayavrata scooped water fromthe river, he found a tiny fish inside his kamandalam , then he tried to leave it back into river , the fish entreated the Stayavrata , not to leave him in the river as it would be eaten up by big fish. The fish grew bigger and bigger that , lakes were not enough, so the king thought of leaving it in the ocean as he had no other way, when he reached ocean, Fish again pleaded the king not to leave in the ocean, as it will be eaten by big fish. The king got suspicious and realised that it is Lord Vishnu in the form of fish. When King asked God, why he is in the form of fish? Lord replied his devotee, In a weeks time, the ocean will rise high and inundate the entire universe. Lord Vishnu gave the Satyavrata the knowledge he would require for his role as Manu in the next cycle. At that time a boat will come approaching you , do collect all seeds, Plants, animals, sages, and Vasuki serpant, as required for the next spell of creation and get into the boat and wait for me. As said by lord Vishnu,Pralayam began ,A boat approached satyavrata and all went inside the boat , and a fish with a horn came near and ordered them to tie up the boat to its horn with the help of vasuki serpant as rope.Lord Vishnu,(Matsya) left for fulfilling its mission. Hayagriva saw the gigantic fish approaching him and was overtaken by fear. He held the Vedas tightly in his mouth. But soon the Divine Fish slew him and recovered the Vedas and restored them to Brahma for him to resume the function of Creation at the appropriate time.Thus lord Vishnu saved the mankind from dissolution.
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