Once upon a time, lived a young orphan farmer in the northern part of the Sumatran Island. This area was very dry. The young man lived from farming and fishing. One day he went fishing, he already fishing for half of the day but still not getting any fish yet. So he returned home for the day turns to night, but when he nearly left he saw a big beautiful golden fish, he then caught the fish and brought it home. He intended to cook the fish right away but watched the beauty of this fish he then cancelled his intention. He chose to keep it as pet, and then he placed it in a big pond and feed it. On the next day, like usual, he went to his farm, and on the noon he comeback home, to have lunch. But when he arrived in his house he was very startled for the meal had prepared to be eaten. He then fears that the fish might be stolen, and then hastily he ran to the back of his house.
However, the fish was still in place, for a long time he thinks, “Who cooks those meals”, but because his is very hungry, he ate those meals. But this incident continued to occur again repeatedly, every time he came home for lunch, the meals are prepared on the table. Then one day this young man made a strategy to find out who cooks those meals, the next day he then began to commence his strategy, he then hide around the trees close to his house. He was waiting for a long time, but the smoke in his kitchen still has not been seen, and when he then intended to return home, he began to see the smoke in the kitchen.
"Hey woman, who are you, and where are you came from?” the woman began to drop tears, and then the young man saw his fish was no longer in the pond. He asked the woman, “hey woman, where is the fish in that pond?” the Woman cried intensely, but this young man continued to ask and finally the woman answers, “I was the fish that was caught by you”. The young man then startled, but because he felt that he had hurt the feelings this woman, then he said, “Hey woman, did you want to become my wife??” the Woman then startled, he stay quiet, then the young man said “Why are you silent??” Then the woman said, “I wanted to become your wife. But with one condition.” ”What is the condition?” the young man quickly asked, the woman then said, “In the future if our child was born and grew, never even once you said that he/she was anakni Dekke (child of a fish) ”. The young man then agreed to that condition and swore he will never say it.
Then they were married and granted a child. When the child was 6 years old, this child turn to be very naughty. Then one day the mother told her child to deliver meals to his father field, the child then went to deliver rice to his father. But in the middle of the trip, this child was felt hungry, then the child opened food package for his father, and ate the food. After finished eating, the child then wrapped it back and continued the trip to his father's field. On arrival the child gave the food package to the father, the father was very happy, the father then sat and immediately opened the food package that was sent by his wife to be carried by his child. But he was very startled when he opened the package there is only bones remained. The father then asked his child “Hay my child, why there are only bones left in this package??” And the child answers,” In my trip I felt hungry, so I ate the food.” Listened to that the father was very angry, he then slap his child and said, "Botul maho anakni dekke (Why you child of a fish),". The child is then ran home crying and ask to his mother “Mak, Olo do na in dokkon amangi, botul do au anakni dekke? (Mother, is it true what father said, that I am a child from a fish?) ” Heard his child's words his mother was startled. While dropping tears and saying in her heart, “My husband has violated his swore, and now I must return to my place.” Then the sky was suddenly become dark followed with lightning, thunder, storm, and rain. The child and the mother disappeared, from their footprint emerged a spring that flowed water as swiftly as possible. Until this area was turned into a lake, that was named as “Tuba Lake” the lake without mercy, but because of the bataks was difficult to say “Tuba”, then this lake was mentioned as. LAKE TOBA. According to the local Citizen, the mother return as a huge fish (the lake guardian), and until today no one is able to measure the depth of this lake. Many tourists that tried to dive into the lake but never return. The lake depth in the book is only estimation not as a fact.