SB 5.24.25

yasyānudāsyam evāsmat-pitāmahaḥ kila vavre na tu sva-pitryaṁ yad utākutobhayaṁ padaṁ dīyamānaṁ bhagavataḥ param iti bhagavatoparate khalu sva-pitari.
Synonyms: 
yasya — of whom (the Supreme Personality of Godhead); anudāsyam — the service; eva — certainly; asmat — our; pitā-mahaḥ — grandfather; kila — indeed; vavre — accepted; na — not; tu — but; sva — own; pitryam — paternal property; yat — which; uta — certainly; akutaḥ-bhayam — fearlessness; padam — position; dīyamānam — being offered; bhagavataḥ — than the Supreme Personality of Godhead; param — other; iti — thus; bhagavatā — by the Supreme Personality of Godhead; uparate — when killed; khalu — indeed; sva-pitari — his own father.
Translation: 
Bali Mahārāja said: My grandfather Prahlāda Mahārāja is the only person who understood his own self-interest. Upon the death of Prahlāda’s father, Hiraṇyakaśipu, Lord Nṛsiṁhadeva wanted to offer Prahlāda his father’s kingdom and even wanted to grant him liberation from material bondage, but Prahlāda accepted neither. Liberation and material opulence, he thought, are obstacles to devotional service, and therefore such gifts from the Supreme Personality of Godhead are not His actual mercy. Consequently, instead of accepting the results of karma and jñāna, Prahlāda Mahārāja simply begged the Lord for engagement in the service of His servant.
Purport: 

Śrī Caitanya Mahāprabhu has instructed that an unalloyed devotee should consider himself a servant of the servant of the servant of the Supreme Lord (gopī-bhartuḥ pāda-kamalayor dāsa-dāsānudāsaḥ). In Vaiṣṇava philosophy, one should not even become a direct servant. Prahlāda Mahārāja was offered all the blessings of an opulent position in the material world and even the liberation of merging into Brahman, but he refused all this. He simply wanted to engage in the service of the servant of the servant of the Lord. Therefore Bali Mahārāja said that because his grandfather Prahlāda Mahārāja had rejected the blessings of the Supreme Personality of Godhead in terms of material opulence and liberation from material bondage, he truly understood his self-interest.