Nrsimhadeva is Krishna’s half-man and half-lion incarnation. After Krishna’s incarnation as a boar, Varahadeva, killed the demon Hiranyaksha, the demon’s younger brother, Hiranyakashipu, was determined to get revenge and conquer the universe. He performed severe austerities to get the attention of Brahma, and asked to be granted immortality. Brahma, the engineer of the universe, was himself a mortal being and so could not grant him immortality. But he did give Hiranyakashipu the boons that he could not be killed by any man or animal, by any weapon or anything living or dead, during the day or night, inside or outside, on the land or in the sea or sky.
Although seemingly invincible, when Hiranyakashipu tormented his youngest son Prahlada, a pure devotee of the Lord, Krishna burst out of a palace column as Nrisimhadeva. By killing Hiranyakashipu in the form of a half-man and half-lion, with his fingernails, at dusk, in the threshold of the palace and on his lap, Nrisimhadeva simultaneously respected the boons given by Brahma and saved His dear devotee Prahlada Maharaja.
Lord Narasimha Deva removes the obstacles in the path of devotional service. Devotees who pray to Him are always protected from all kinds of calamities.