Image: Dolls of India
Lord Vishnu incarnated as a fish to retrieve the Vedas from the Asura Hayagriva, who had stolen it from Brahma.
It so happened that Brahma was about to fall asleep at the end of a kalpa. The earth was submerged in water due to Naimitika pralaya. Kalpa is a period of the universe which runs to billions of years and is considered as one day of Brahma. At the end of this period there is a deluge and the earth is submerged in water. This is called as a pralaya. A pralaya happens periodically at the end of every Kalpa and is so called as Naimitika pralaya or periodical deluge. At one such time the asura Hayagriva stole the Vedas from Brahma and hid it under water.
King Satyavrata was a noble, sagely and pious king ruling a place Dramila at that time. As he was performing his morning ablutions in the river, a small fish came into his cupped palm along with the water. He was about to drop the fish back into the river, when the fish spoke to him requesting him not to drop him back into the river as the bigger fishes might eat him up. The king realising that this is no ordinary fish put him in his kamandalu (pot with handle containing water) and took him along. He placed him in a tank at his palace. Soon the fish outgrew the tank, and then a pond.
The king felt that at this rate the fish cannot be contained and therefore dropped him into the sea by his yogic powers. Again the fish spoke to him asking him not to leave him in the ocean. Satyavrata understood that this is some disguise of the lord Narayana and responded saying that “Surely you are no ordinary fish. You are Lord Narayana who has taken this form for a purpose. Please tell me the purpose of your taking this form.” The Lord then reveals the truth to him and lets him know that within 7 days a Mahapralaya will engulf the world. A boat will then appear. Satyavrata should get into the boat along with the saptarishis (seven rishis) and carry with him all the medicinal herbs and seeds of plants. The world will be plunged in darkness; it’s the light emanating from the seven rishis that will show him the way. The lord will then appear in the ocean in his fish form. When they find him they should tie their boat to his horns and they will come out safely through the deluge.
Accordingly Satyavrata spent the seven days in prayer and meditation. Meanwhile there was a deluge. On the appointed day a boat appeared. Satyavrata did as instructed by the fish. The Rishis were constantly chanting the lord’s name and singing his praises. In the mid ocean they spotted the huge fish that was the lord and tied their boat to the horns of the fish. While the boat tossed and turned in the turbulent ocean waters, the voyagers were not worried because it was the lord who was pulling them through. (Subtle meaning…The lord is the boat that can pull us through the ups and downs of the ocean of life). The voyage lasted for one night of Brahma. During this period at the behest of Satyavrata, the Lord imparted the Brahma vidya to him.
From under the ocean the lord fought the Asura Hayagriva, retrieved the Vedas and restored it to Brahma by the end of the pralaya.
Ref: Srimad Bhagawatam by Kamala Subramaniam
Narayaneeyam by S.N. Sastri