Once upon a time, there lived a poor Brahmin named Dev Sharma with his wife in a small village. The Brahmin used to perform puja in religious functions taking place in nearby villages. They had no children. They offered prayers to god for a child. At last, a son was born to them.
The Brahmin's wife had a mongoose as her pet. The mongoose was very playful. He used to guard the Brahmin's house and also looked after the baby, while it slept in the cradle.
Once, some people came to invite the Brahmin for performing puja in their house. The Brahmin was in a quandary. Should he go to perform puja or stay home to look after his baby? His wife had also gone to fetch water from the well situated on the outskirts of the village.
The Brahmin didn't want to leave the baby all alone in the house, even though the mongoose was sitting there beside the cradle like a baby sitter. He was in a state of perplexity. But at last he buckled under the pressure and went to the nearby village to conduct the religious ceremony, leaving the baby all alone in the house.
The mongoose still sat beside the cradle guarding the baby. Suddenly, he saw a big black snake crawling towards the cradle. Being a natural enemy of snakes and also having the responsibility of guarding the baby, he pounced upon the snake. After a fierce fighting with the snake the mongoose killed it.
But the mouth and paws of the mongoose were smeared with the snake's blood. The mongoose was happy that he had done his duty faithfully and had saved the baby from the snake. He ran to the main entrance of the house and sat there waiting for his master's wife to come back. He thought that she would be highly impressed with his performance and shall reward him suitably.
After sometime, the Brahmin's wife came along with the water pitcher on her head. She saw the paws and mouth of the mongoose smeared in blood.
She thought that the mongoose had killed her baby. In a fit of rage, she threw the heavy water pitcher on the head of the mongoose. The mongoose died on the spot.
The Brahmin'os wife now went running inside the house. There she saw a big black snake lying dead. The baby was sleeping safe in the cradle. Now she realised that she was greatly mistaken, and the mongoose had, in fact, saved her child. She began repenting and weeping. She had killed her faithful pet without knowing what had really happened.