Once upon a time, A great King Parikshit had died due to snake bite by snake called Takshak. To seek revenge of his father’s death Janmejay, who is known to be the first ruler of Kall yug, performed a nag yajna, which would kill and get rid of all the snakes in the universe. As the Yajna proceeded, many snakes had already died and only a few remained.
Vasuki, the king of snakes was very worried and feared for the continuity of his species. He went to his sister Jaratkarvand and said “ Sister I feel very weak from the inside and have a feeling of burning. I feel like I am being pulled into the fire of the Yajna. I was anticipating such an incidence earlier, and it was for this day that I got you married to Rishi Jaratkaru. Now, you are the only hope for our race and who can stop this Yajna from proceeding. According to the prophecy of Lord Brahma, your son Aasteek will be able to stop the yajna. Even though he is a small boy, but he is a great scholar of the Vedas and is loved by all his elders. I request you to remind him of the love and care that our race has given him. He is our only hope otherwise all snakes will disappear.”
Hearing these words Jaratkaru went to her son and explained the situation to him. Heartfelt for all the snakes, Aasteek went to Vasuki and assured him that he should not fear anymore as he would visit King Janmejeya and impress him with his knowledge and ask him to stop the yajna.
Aasteek immediately left for the venue of the yajna but as he reached there he was not allowed to enter by the sentries. So he started singing hymns in praise of the yajna and all the present eminent people who had attended the yajna.
Hearing the sweet voice of Aasteek, King Janmejeya and the other dignitaries present at the yajna were impressed. King Janmejaya wanted to grant the boy a wish, but he counseled the other sages that what he should do. All the Brahmins present, unanimously agreed that since the boy was a great scholar and a Brahmin he should be awarded for his knowledge. After the counsel, Janmejeya asked the Brahmins to continue to chant the most potent of all mantras so that Takshak is soon doused in the fire. As takshak was getting closer to the fire of the yajna with every passing minute of the yajna, then Janmejaya turned to Aasteek to ask for his wish.
Without wasting any time, Aasteek asked to stop the Yajna that Janmejaya had begun to wipe out the entire snake race so that those who are left can survive. Janmjaya begged the boy that he ask for anything but not to stop the yajna as it was his only aim to kill all the snakes. But the boy was persistent about his wish and did not move.
Finally, Janmejaya had to relent and he stopped the yajna putting the fires out.