A mahā-bhāgavata devotee, or the Lord Himself, is pleased to find a fit candidate for understanding the inexpressible meanings of bhakti-yoga. The transference of knowledge in Kṛṣṇa consciousness is, in one sense, very straightforward. Śrīla Prabhupāda used to criticize the story of a disciple who said that he received knowledge from his guru by a method similar to receiving an electric shock. Lord Kṛṣṇa taught Arjuna by the process of question and answer, and one may still faithfully study Kṛṣṇa's lucid words for enlightenment in bhakti-yoga. As always, therefore, the process of receiving the teachings of bhakti-yoga is to serve the spiritual master, inquire from him, and hear his paramparā instructions.

And yet learning the science of bhakti-yoga is not an ordinary transference of knowledge, as when a professor writes lessons on a blackboard and his students write them down. Only if the spiritual teacher is actually potent and the students are purely receptive can the teacher plant the seed of bhakti (the bhakti-latā-bīja) in their hearts. How that seed fructifies in a student's heart is not understandable by material calculations. Śrīla Prabhupāda writes,

Human reason fails to understand how by serving the devotee bhāgavata or the book bhāgavata one gets gradual promotion on the path of devotion. But actually these are the facts explained by Śrīla Nāradadeva, who happened to be a maidservant's son in his previous life. [SB 1.2.18, purport]

Although the guru-disciple relationship is a subtle one, it can be understood by the standard qualifications of both persons. For example, although Nārada was a young boy, the bhaktivedānta sages who visited his home found him a fit candidate, and so they blessed him. Nārada recalls the incident:

Although they were impartial by nature, those followers of the Vedānta blessed me with their causeless mercy. As far as I was concerned, I was self-controlled and had no attachment for sports, even though I was a boy. In addition, I was not naughty and I did not speak more than required. [SB 1.5.24]

The sages at Naimiṣāraṇya praised the speaker Sūta Gosvāmī in a similar way:

And because you are submissive, your spiritual masters have endowed you with all the favors bestowed upon a gentle disciple. Therefore you can tell us all that you have scientifically learned from them. [SB 1.1.8]

For realization of the most advanced spiritual knowledge, such as the pastimes of Lord Caitanya, the devotee has to be extremely well qualified. As Kṛṣṇadāsa Kavirāja says, "Unto one who is able to understand, Śrī Caitanya Mahāprabhu has shown mercy by giving him the association of the servant of His own servant" (Cc. Madhya 2.83). The spiritual knowledge Lord Caitanya conveyed to Rāmānanda Rāya was so completely out of the range of mundane vision that Lord Caitanya said that "only a madman can understand it." Lord Caitanya confided to Rāmānanda:

Please rest assured that I have nothing to hide from you. Even if I do try to hide something from you, you are such an advanced devotee that you can understand all My secrets.... The facts which I have disclosed to you cannot be understood by materialistic people. When they hear of this, they will simply laugh at Me. You can understand this yourself and keep it to yourself. [Teachings of Lord Caitanya, p. 346]

In his later years, when Lord Caitanya exhibited His pastimes of entering intensely into the mood of Rādhārāṇī in separation from Kṛṣṇa, He shared this rasa only with His most intimate devotees, such as Rāmānanda Rāya and Svarūpa Dāmodara. They could understand the Lord's moods, which sometimes produced displays of seeming madness and which ordinary words or behavior could not express. "Only a person on the level of Svarūpa Dāmodara Gosvāmī can fully know what Lord Śrī Caitanya Mahāprabhu tastes in His love for Kṛṣṇa" (Cc. Antya 18.22).

Nārada Muni's point in this sūtra is that even when bhakti cannot be expressed in words, its essence can be manifest by the ecstatic symptoms of one great soul and appreciated by other great souls. When Lord Caitanya felt an ecstatic mood coming on but there were nondevotees present, He would try to restrain His outward manifestations of ecstatic love. For example, when Lord Caitanya first met Rāmānanda Rāya, they embraced and almost lost consciousness, overwhelmed by the ecstatic love of Kṛṣṇa and the gopīs. But some stereotyped, ritualistic brāhmaṇas were present at that time, and they doubted the propriety of the interaction between the Lord and Rāmānanda. According to Kṛṣṇadāsa Kavirāja, "While the brāhmaṇas were thinking in this way about the activities of Śrī Caitanya Mahāprabhu and Rāmānanda Rāya, Lord Caitanya saw the brāhmaṇas and restrained His transcendental emotions" (Cc. Madhya 8.28).

We should not think that only a fixed number of intimate devotees can receive the bhakti-śakti, and that we are obviously not among the chosen. The ācāryas advise us that if we keep striving, one day each one of us may uncover our original, dormant Kṛṣṇa consciousness. Moreover, Lord Caitanya surpassed all previous ācāryas, bhaktas, and incarnations by very liberally distributing intimate love of God. Anyone who is receptive to the saṅkīrtana movement of Lord Caitanya can therefore be quickly elevated to the platform where he can understand the inexpressible experiences of bhakti-yoga. In appreciation for this liberality of Lord Caitanya, Rūpa Gosvāmī composed a prayer:

namo mahā-vadānyāya kṛṣṇa-prema-pradāyate
kṛṣṇāya kṛṣṇa-caitanya nāmne gaura-tviṣe namaḥ

"I offer my respectful obeisances unto the Supreme Lord, Śrī Kṛṣṇa Caitanya, who is more magnanimous than any other avatāra, even Kṛṣṇa Himself, because He is bestowing freely what no one else has ever given—pure love of Kṛṣṇa."