Hiranyakasipu had four wonderful, well-qualified sons, of whom the one named Prahlada was the best. Indeed, Prahlada was a reservoir of all transcendental qualities because he was an unalloyed devotee of the Personality of Godhead

Expressions researched:
"Hiranyakasipu had four wonderful, well-qualified sons, of whom the one named Prahlada was the best. Indeed, Prahlada was a reservoir of all transcendental qualities because he was an unalloyed devotee of the Personality of Godhead"

Srimad-Bhagavatam

SB Canto 7

Hiranyakasipu had four wonderful, well-qualified sons, of whom the one named Prahlada was the best. Indeed, Prahlada was a reservoir of all transcendental qualities because he was an unalloyed devotee of the Personality of Godhead.

SB 7.4.30, Translation and Purport

Hiranyakasipu had four wonderful, well-qualified sons, of whom the one named Prahlada was the best. Indeed, Prahlada was a reservoir of all transcendental qualities because he was an unalloyed devotee of the Personality of Godhead.

yasyāsti bhaktir bhagavaty akiñcanā

sarvair guṇais tatra samāsate surāḥ

"In one who has unflinching devotional faith in Kṛṣṇa, all the good qualities of Kṛṣṇa and the demigods are consistently manifest." (SB 5.18.12) Prahlāda Mahārāja is praised herein for having all good qualities because of worshiping the Supreme Personality of Godhead. Therefore, a pure devotee, who has no motives, has all good qualities, material and spiritual. If one is spiritually advanced, being a staunch, liberal devotee of the Lord, all good qualities are manifest in his body. On the other hand, harāv abhaktasya kuto mahad-guṇāḥ: if one is not a devotee, even if he has some materially good qualities, they have no value. That is the verdict of the Vedas.