After the death of his brother Hiranyaksha, Hiranyakashipu developed a great hatred for Lord Vishnu. Desiring to avenge his brother's death and to enjoy his power forever, he decided to pray to Lord Brahma to grant him boons.
So he stood on one leg with his arms stretched above his head and meditated on Lord Brahma, for a very long time. Finally, pleased with the demon, Lord Brahma appeared and told Hiranyakashipu that he would grant him any boon.
Immediately the demon said, "O Lord Brahma, please grant me the boon to live forever!"
But Brahma replied, "I do not have the power to grant you everlasting life. Ask me for something else that I can give you."
The cunning demon then changed his wish, thinking that he could trick Brahma to give him what he wanted - everlasting life, in some other way.
He said, "Lord, grant that I may not be killed by any demon or human or demigod. Grant that I may not be killed during the day or night. Grant that I may not be killed by any weapon, and neither inside nor outside."
Lord Brahma granted Hiranyakashipu his boons and left.
Hiranyakashipu could not be defeated by anyone after he was blessed by Brahma. The demon conquered the heaven and earth. He chased the demigods from their homes in the heavens and treated the people very cruelly.
While Hiranyakashipu was away meditating, the demigods attacked his kingdom and entered his palace.
His wife Kayadhu, who was about to have a child, was taken as a prisoner. But before Indra could kill her, Narada Muni stopped him and took her to his ashrama.
There, Narada Muni taught her all about how to serve God. The child in her womb also heard all these teachings. Narada Muni knew that this child was actually a great devotee of Lord Vishnu, although his father was a demon.
When the child was born, he was named Prahlada.
Prahlada was always talking about and thinking of Lord Vishnu.
Hiranyakashipu was very angry that his son was always praising and worshipping Lord Vishnu, whom the demon thought was his enemy. He told the teachers in the school to make Prahlada forget Vishnu and learn about how to make money and enjoy life.
But whatever they taught him, Prahlada would not forget to praise Lord Vishnu.
Hiranyakashipu began to see his five year old son as his enemy because Prahlada never changed.
So the demon king tried to kill Prahlada in different ways. He had him boiled in oil, but nothing happened to the boy! He had him put in a pit of snakes, but they did not harm him!
Prahlada was thrown from a cliff but Lord Vishnu saved him. Mad elephants were set on him, but their tusks broke when they tried to pierce his body!
Hiranyakashipu was mad with anger that Prahlada could neither be killed nor would the boy stop praising Lord Vishnu. He called him to his court and asked him, "Where do you get your power from, my son?"
Prahlada answered, "The Supreme Lord Vishnu is the one who gives us all our power, my dear father."
Hiranyakashipu then asked the boy, "Where is your Lord Vishnu to be found?" And Prahlada replied, "He is everywhere, father.'
Hiranyakashipu thought that he could kill Lord Vishnu, so he drew out his sword and pointed at a pillar near him. "Is Vishnu here?" he asked Prahlada.
"Yes, father, He is also in that pillar," said Prahlada.
Then Hiranyakashipu struck the pillar with his sword saying, "Then I shall kill Him!"
As the sword struck the pillar, a great roar could be heard from inside the pillar. The pillar cracked open and broke and from it emerged a huge form of Lord Narasimha. He was the half lion, half human form of Lord Vishnu, who had come to save His young devotee Prahlada from the great demon Hiranyakashipu.
His roar sounded like a thousand lions roaring together. Lord Narasimha was dressed in yellow garments.
He wore a crown on His head. His mane was the colour of gold. His nails were like shining claws. He had beautiful necklaces on His chest and His teeth were sharp and white.
He was very furious and slowly stepped out of the pillar and went towards Hiranyakashipu.
The demon was frightened when he saw Lord Narasimha. But in his pride, he laughed loudly. He had thought that he could kill Lord Vishnu but never expected to see this form of the Lord.
He could not accept that he would be defeated easily by the Lord and started to wield his sword to keep Lord Narasimha away from him.
A great fight followed and at twilight, when Lord Narasimha had had enough of playing with the demon, He grabbed hold of Hiranyakashipu and dragged him to the doorstep of the courtroom.
Then, laying the demon on His lap, Lord Narasimha ripped his stomach with His nails and took the life out of Hiranyakashipu. In this way, Lord Narasimha killed the demon who had tried to trick Brahma into giving him immortality.
The Lord killed Hiranyakashipu at twilight, which is neither day nor nighttime. He was killed at the doorstep, which is neither inside nor outside.
He was killed on the lap of the Lord, which is neither in heaven nor on earth. He was killed by the nails of the Lord, which are not weapons. He was killed by the half lion, half man form of Lord Narasimha, who is neither human nor animal.
In this way, the wonderful form of Lord Vishnu as Narasimha saved His dear devotee from the torture of Hiranyakashipu.