There was once a great demon who was overwhelmed with rage: his brother Hiranyaksa had just been killed by the incarnation of Vishnu known as Lord Varaha. Thus he became very determined to become the emperor of the entire universe. In order to increase his power, he performed very powerful austerities. This penance was so severe that it disturbed the demigods. In fact, the demigods requested Lord Brahma to stop him. The chief of the demigods, Lord Brahma, therefore descended to pacify him by granting him a wish.
"Please grant that I not be killed by any created living being," commanded Hiranyakasipu, "that I not die inside or outside any residence, during the daytime or night, nor on the ground or in the sky; that I not be killed by any being created by you, nor by any weapon, nor by any human being or animal indeed that I not meet death from any entity, either living or non-living; that I have no competitor; that I have sole lordship over all living entities and presiding deities, and that I acquire all mystic powers."
After Brahma had granted him all these requests, Hiranyakasipu very swiftly conquered all the planets in the universe, took up residence in the lavish palace of King Indra, and forced the demigods to bow down to his feet. He even stole the sacrificial oblations meant for the demigods. Intoxicated physically by wine and mentally by power, Hiranyakasipu ruled the universe very severely.
During this time his queen, Kayadhu, returned to the palace of her husband and bore him a son, Prahlada. He was a reservoir of all transcendental qualities because he was a pure devotee of Lord Visnu. Determined to understand the Absolute Truth, he had full control over his senses and mind. He was kind to all living creatures and the best friend of everyone. Toward respectable persons he behaved just like a menial servant, to the poor he was like a father, and to his equals he was always like a sympathetic brother. Always very humble, he considered his teachers and spiritual masters to be as good as the Lord Himself. Indeed, he was completely free of any pride that might have arisen from his good education, riches, beauty, and aristocratic birth.
Hiranyakasipu wanted to raise his son to be a powerful demon, but Prahlada only wanted to learn about devotional service to Lord Visnu. After Prahlada attended school for some time, Hiranyakasipu took him on his lap and affectionately inquired, "My dear son, please tell me about your favorite subject in school."
Fearlessly, Prahlada said, "Hearing (sravanam) and chanting (kirtanam) about the holy name, form, qualities, paraphernalia, and pastimes of the Supreme Lord; remembering (smaranam) them; serving the lotus feet of the Lord (pada-sevanam); offering the Lord respectful worship with sixteen types of paraphernalia (arcanam); offering prayers to the Lord (vandanam); becoming His servant (dasyam); considering the Lord one’s best friend (sakhyam); and surrendering to Him (atma-nivedanam, in other words, serving Him with body, mind and words); these nine processes are known as pure devotional service, and I consider anyone who has dedicated his life to service of Lord Visnu through these nine methods to be the most learned person, for he has acquired complete knowledge."
Blinded by anger, Hiranyakasipu threw Prahlada from his lap onto the ground. "Servants! Take him away and kill him at once!" he screamed. However, Prahlada just sat silently and meditated on the Personality of Godhead, and the demons’ weapons had no effect on him. Seeing this Hiranyakasipu became fearful and contrived various ways to kill his son. His servants threw Prahlada beneath an elephant’s feet; they cast him into the midst of huge, fearful snakes; they cursed him with destructive spells; they hurled him from a hilltop; they gave him poison; they starved him; they exposed him to severe cold, winds, fire and water; they threw heavy stones to crush him. Hiranyakasipu even sent his sister Holika to burn him, but instead she herself was burned. But throughout these trials Prahlada was simply absorbed in thoughts of Lord Visnu, and thus he remained unharmed. Hiranyakasipu became very anxious about what to do next.
"You say there is a being superior to me," said Hiranyakasipu, "but where is He? If He is present everywhere, then why is He not present in this pillar you see before you? Do you think He is in this pillar?" "Yes," Prahlada answered, "He is there."
Hiranyakasipu's rage flared more and more. "Because you are speaking so much nonsense, I shall now sever your head from your body. Now let me see your most worshipable God come to protect you. I want to see it." Cursing him again and again, Hiranyakasipu took up his sword, got up from his royal throne, and with great anger struck his fist against the column.
Then from within the very pillar that he had singled out came a wonderful half-man, half-lion form never before seen. The Lord’s form was extremely fearsome because of His angry eyes, which resembled molten gold; His shining mane, which expanded the dimensions of His fearful face; His deadly teeth; and His razor-sharp tongue. Lord Nrsimha then proceeded to battle with the wasp-like Hiranyakasipu.
Finally at twilight, Lord Nrsimha captured Hiranyakasipu and placed him in His lap on the doorway of the assembly hall. As He began ripping the demon to pieces with His many, many hands, Lord Nrsimha’s mouth and mane became sprinkled with drops of blood, and His fierce eyes, full of anger, were impossible to look at. Licking the edge of His mouth with His tongue, the Supreme Lord decorated Himself with a garland of intestines taken from Hiranyakasipu's abdomen. Lord Nrsimha uprooted Hiranyakasipu’s heart and finally threw him aside and destroyed an army of Hiranyakasipu’s faithful followers.
By His transcendental cleverness, Lord Nrsimhadeva was able to kill Hiranyakasipu without contradicting any of Lord Brahma’s benedictions. The execution took place neither inside nor outside, but in the doorway; neither on land nor in sky, but on the Lord’s lap; neither during the day nor during the night, but at twilight; neither by man, beast, or demigod nor by any created being, but by the Personality of Godhead; and not by any weapon, but by the Lord's own lotus hand, relieving the whole universe of Hiranyakasipu’s demonic activities.
Having been protected by the Lord, Prahlada Maharaja offered many prayers in a voice that faltered with love:
"My dear Lord Nrsimhadeva, please, therefore, allow Your angry feature to diminish, now that my evil father Hiranyakasipu has been killed . . . [The saintly persons] will always remember Your auspicious and fearsome incarnation, for it frees them from fear. In this way, my Lord, You appear in various incarnations as a human being, an animal, a great saint, a demigod, a fish or a tortoise, thus maintaining the entire creation in different planetary systems and killing the demoniac principles."
Adapted from Srimad Bhagavatam, 7th Canto
Bhaktivedanta Book Trust. HDG A.C. Bhaktivedanta Swami Srila Prabhupada.