ayam me bhratr-ha so ’yam
hitva svan suhrdo ’dhamah
pitrvya-hantuh padau yo
visnor dasavad arcati
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
This boy Prahlada is the killer of my brother, for he has given up his family to engage in the devotional service of the enemy, Lord Visnu, like a menial servant.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Hiranyakasipu considered his son Prahlada Maharaja to be the killer of his brother because Prahlada Maharaja was engaged in the devotional service of Lord Visnu. In other words, Prahlada Maharaja would be elevated to sarupya liberation, and in that sense he resembled Lord Visnu. Therefore Prahlada was to be killed by Hiranyakasipu. Devotees, Vaisnavas, attain the liberations of sarupya, salokya, sarsti and samipya, whereas the Mayavadis are supposed to attain the liberation known as sayujya. Sayujya-mukti, however, is not very secure, whereas sarupya-mukti, salokya-mukti, sarsti-mukti and samipya-mukti are most certain. Although the servants of Lord Visnu, Narayana, in the Vaikuntha planets are equally situated with the Lord, the devotees there know very well that the Lord is the master whereas they are servants.