The story follows: a long time ago there was a king named Great Vehicle. He ruled over many thousand settlements had three sons - the eldest was called Great Sound, the middle, Great Deity and the youngest, Great Sentient Being (Mahasattva). From childhood, the youngest son had a loving and compassionate nature. One day, while walking in the woods the three boys came across a tigress who had just given birth to cubs. She was so exhausted by days of hunger, thirst, and effort that she was on the verge of eating her own young.
The youngest prince said, "This tigress is suffering so much that she is at the edge of death, and would even desire to eat her own offspring. What does the tigress eat?" The two elder brothers replied "She eats freshly killed meat and drinks blood." Then he said "Who has such strength that they would save her life by giving her these things?" The two brothers replied, "Surely, nobody!"
As they continued on, the youngest thought: "For a long time I have been wandering in samsara wasting innumerable bodies and lives. I have given up my body sometimes to desire, sometimes to anger and sometimes to ignorance. What is the use of this body which for the sake of Dharma has not even once engaged in good?" He told his brothers to go ahead and returned to the lair of the tigress. He lay down in front of her, but she was too weak to eat. So, he took a sharp branch and made blood flow from his body and let the tigress lick it. She then opened her mouth and completely devoured the flesh of his body.
At that same moment, the queen dreamed that three pigeons had been flying, and a falcon had caught the youngest. She woke up immediately, terrified, and told the king, "I have been told that a pigeon is the soul of a son. I dreamed that a falcon caught the youngest of three pigeons, so something unfortunate has certainly befallen the most beloved of my sons." When the two elder brothers returned they reported that the youngest prince had sacrificed his body to the tigress. The entire entourage proceeded swiftly to the place where the prince had died. They saw nothing but bones and blood.
Having died in this place, the Prince Mahasattva was reborn in the Tushita realm of gods. He wondered, "Through what positive action was I born here?" In a forest, he saw the bones he had left behind, and his parents who were weighed down by great grief.
He descended from heaven and reassured his parents saying "I was your son Mahasattva. Having fed the tigress with my body, I was born in the Tushita realm of gods. Great King, know this! Whatever has come into existence will meet with destruction in the end. When there is arising, there is certainly destruction. If they engage in negative actions, sentient beings will fall into hell. If they engage in virtuous ones, they will take rebirth in the higher realms. Arising and destruction affects everything. Why then are you experiencing an ocean of suffering just because of me? Strive for virtue!"
Being a little comforted, the king and queen made a casket of seven precious jewels, put the prince's bones inside it and buried it. Above the mound, they erected a stupa, today known as Namo Buddha.