He (Hiranyakasipu) then asked Brahma for the benediction of becoming amara, by which one does not die. Brahma said that he could not award the benediction because even he, the material creator who rules all planets, is not amara
Other Books by Srila Prabhupada
From the Purāṇas we learn of the activities of Hiraṇyakaśipu, a king who was very much advanced materially. Wanting to conquer cruel death by his material acquisitions and the strength of his nescience, he underwent a type of meditation so severe that the inhabitants of all the planetary systems became disturbed by his mystic powers. He forced the creator of the universe, the demigod Brahmā, to come down to him. He then asked Brahmā for the benediction of becoming amara, by which one does not die. Brahmā said that he could not award the benediction because even he, the material creator who rules all planets, is not amara. As confirmed in the Bhagavad-gītā (8.17), Brahmā lives a long time, but that does not mean he is immortal.
Hiraṇya means "gold," and kaśipu means "soft bed." This cunning gentleman Hiraṇyakaśipu was interested in these two things—money and women—and he wanted to enjoy them by becoming immortal. He asked from Brahmā many benedictions in hopes of indirectly fulfilling his desire to become immortal. Since Brahmā told him that he could not grant the gift of immortality, Hiraṇyakaśipu requested that he not be killed by any man, animal, god or any other living being within the 8,400,000 species. He also asked that he not die on land, in the air or water, or by any weapon. In this way Hiraṇyakaśipu foolishly thought these guarantees would save him from death. Ultimately, however, although Brahmā granted him all these benedictions, he was killed by the Personality of Godhead in the form of Nṛsiṁha, the Lord's half-lion, half-man incarnation, and no weapon was used to kill him, for he was killed by the Lord's nails. Nor was he killed on the land, in the air or in the water, for he was killed on the lap of that wonderful living being, Nṛsiṁha, who was beyond his conception.
The whole point here is that even Hiraṇyakaśipu, the most powerful of materialists, could not become deathless by his various plans. What, then, can be accomplished by the tiny Hiraṇyakaśipus of today, whose plans are thwarted from moment to moment?
Śrī Īśopaniṣad instructs us not to make one-sided attempts to win the struggle for existence. Everyone is struggling hard for existence, but the laws of material nature are so hard and fast that they do not allow anyone to surpass them. In order to attain a permanent life, one must be prepared to go back to Godhead.