Srimad-Bhagavatam: Canto 1 - Chapter 1 - Verse 25
धृत्या बलिसम: कृष्णे प्रह्राद इव सद्ग्रह: ।आहर्तैषोऽश्वमेधानां वृद्धानां पर्युपासक: ॥ २५ ॥
dhṛtyā bali-samaḥ kṛṣṇeprahrāda iva sad-grahaḥāhartaiṣo ’śvamedhānāṁvṛddhānāṁ paryupāsakaḥ
This child will be like Bali Mahārāja in patience, a staunch devotee of Lord Kṛṣṇa like Prahlāda Mahārāja, a performer of many aśvamedha [horse] sacrifices and a follower of the old and experienced men.
Bali Mahārāja: One of the twelve authorities in the devotional service of the Lord. Bali Mahārāja is a great authority in devotional service because he sacrificed everything to please the Lord and relinquished the connection of his so-called spiritual master who obstructed him on the path of risking everything for the service of the Lord. The highest perfection of religious life is to attain to the stage of unqualified devotional service of the Lord without any cause or without being obstructed by any kind of worldly obligation. Bali Mahārāja was determined to give up everything for the satisfaction of the Lord, and he did not care for any obstruction whatsoever. He is the grandson of Prahlāda Mahārāja, another authority in the devotional service of the Lord. Bali Mahārāja and the history of his dealings with Viṣṇu Vāmanadeva are described in the Eighth Canto of Śrīmad-Bhāgavatam (Chapter 11-24). Prahlāda Mahārāja: A perfect devotee of Lord Kṛṣṇa (Viṣṇu). His father, Hiraṇyakaśipu, chastised him severely when he was only five years old for his becoming an unalloyed devotee of the Lord. He was the first son of Hiraṇyakaśipu, and his mother’s name was Kayādhu. Prahlāda Mahārāja was an authority in the devotional service of the Lord because he had his father killed by Lord Nṛsiṁhadeva, setting the example that even a father should be removed from the path of devotional service if such a father happens to be an obstacle. He had four sons, and the eldest son, Virocana, is the father of Bali Mahārāja, mentioned above. The history of Prahlāda Mahārāja’s activities is described in the Seventh Canto of Śrīmad-Bhāgavatam.