Bali Mahārāja had already been blessed by his grandfather Prahlāda Mahārāja. Therefore, he was a pure devotee, although born in a family of demons. There are two kinds of highly elevated devotees, called sādhana-siddha and kṛpā-siddha. Sādhana-siddha refers to one who has become a devotee by regular execution of the regulative principles mentioned in the śāstras, as ordered and directed by the spiritual master. If one regularly executes such devotional service, he will certainly attain perfection in due course of time. But there are other devotees, who may not have undergone all the required details of devotional service but who, by the special mercy of guru and Kṛṣṇa — the spiritual master and the Supreme Personality of Godhead — have immediately attained the perfection of pure devotional service. Examples of such devotees are the yajña-patnīs, Mahārāja Bali and Śukadeva Gosvāmī. The yajña-patnīs were the wives of ordinary brāhmaṇas engaged in fruitive activities. Although the brāhmaṇas were very learned and advanced in Vedic knowledge, they could not achieve the mercy of Kṛṣṇa-Balarāma, whereas their wives achieved complete perfection in devotional service, despite their being women. Similarly, Vairocani, Bali Mahārāja, received the mercy of Prahlāda Mahārāja, and by Prahlāda Mahārāja’s mercy he also received the mercy of Lord Viṣṇu, who appeared before him as a brahmacārī beggar. Thus Bali Mahārāja became a kṛpā-siddha because of the special mercy of both guru and Kṛṣṇa. Caitanya Mahāprabhu confirms this favor: guru-kṛṣṇa-prasāde pāya bhakti-latā-bīja (Cc. Madhya 19.151). Bali Mahārāja, by the grace of Prahlāda Mahārāja, got the seed of devotional service, and when that seed developed, he achieved the ultimate fruit of that service, namely love of Godhead (premā pum-artho mahān), immediately upon the appearance of Lord Vāmanadeva. Bali Mahārāja regularly maintained devotion for the Lord, and because he was purified, the Lord appeared before him. Because of unalloyed love for the Lord, he then immediately decided, “I shall give this little dwarf brāhmaṇa whatever He asks from me.” This is a sign of love. Thus Bali Mahārāja is understood to be one who received the highest perfection of devotional service by special mercy.