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The lower body resembles a fish and his upper body a man. He has four hands, in which he holds the attributes of Vishnu. Vishnu came in this incarnation to save the world from a Flood. Vishnu ordered Manu, the forefather of the human nature, to
built a ship (arc) and to fill it with all the animals and plants. During the Flood this arc was pulled by Matsya.
During this Flood Matsya fought also with the demon Hayagriva. Hayagrivah had stolen the Vedas from Brahma and thrown away in the ocean. Matsya won the battle and gave the Vedas to Manu. He also instructed Manu on the true nature of Brahma’s eternal soul – The Brahman – and gave him the doctrine that was inculcated in the Vedas.