After meeting Rūpa and Sanātana Gosvāmī, Śrīman Mahāprabhu returned to Purī. He described the glories of Rūpa and Sanātana to His associates there, who also became eager to meet them. After ratha-yātrā, Mahāprabhu again left for Vṛndāvana. While returning from Vṛndāvana, Mahāprabhu met Rūpa Gosvāmī, who was on his way to Vṛndāvana, and there in Prayāga, for ten days, Mahāprabhu instructed him at the Daśāśvamedha-ghāṭa. These instructions, Rūpa-śikṣā, embody one of the five life airs (pañca-prāṇa) of Caitanya-caritāmṛta.
Śrīman Mahāprabhu desired to manifest the glories and pastimes of Rādhā-Kṛṣṇa in Vraja; He thus empowered Śrīla Rūpa Gosvāmī to fulfill His heart’s desire.
vṛndāvanīyāṁ rasa-keli-vārtāṁ kālena luptāṁ nija-śaktim utkaḥ sañcārya rūpe vyatanot punaḥ sa prabhur vidhau prāg iva loka-sṛṣṭim
Caitanya-caritāmṛta, Madhya 19.1
Before the material creation, Bhagavān enlightened the heart of Brahmā with the knowledge to create and also manifested the Vedic wisdom. Likewise, anxious to re-manifest Rādhā-Kṛṣṇa’s pastimes in Vṛndāvana, Mahāprabhu infused the heart of Rūpa Gosvāmī with spiritual power. By this potency, Rūpa Gosvāmī revived the vraja-līlā that had practically been lost to memory and thus he spread kṛṣṇa-bhakti throughout the world.
kṛṣṇa-tattva-bhakti-tattva-rasatattva-prānta saba śikhāila prabhu bhāgavata-siddhānta
Caitanya-caritāmṛta, Madhya 19.116
Śrī Caitanya Mahāprabhu taught Śrīla Rūpa Gosvāmī the ultimate limit of the truth about Lord Kṛṣṇa, the truth about devotional service and the truth about transcendental mellows, culminating in conjugal love between Rādhā and Kṛṣṇa. Finally He told Rūpa Gosvāmī about the ultimate conclusions of the Śrīmad-Bhāgavatam.
Śrīman Mahāprabhu taught Rūpa Gosvāmī: “There are 8,400,000 species of life. Within these life forms, countless jīvas are wandering in this universe. The jīva is an extremely subtle particle of spirit. It cannot be measured by material calculation; but still, to help people understand something about the nature of the soul, scripture describes the size of the soul to be like the divided part of one ten-thousandth of a tip of hair. The species of life are divided into moving and non-moving life forms. Of human beings, most do not follow dharma, and of those who do, most only give lip-service to dharma while committing all sorts of sinful activities. Out of the followers of dharma most follow karma, jñāna, or yoga, and only out of millions of such persons, can one find a pure devotee of Kṛṣṇa. Amongst the countless living beings wandering in material existence, an extremely fortunate soul comes in touch with a pure spiritual master, sent by Kṛṣṇa’s grace from His spiritual kingdom. By the mercy of guru and Kṛṣṇa, such a person receives the seed of the devotional creeper.
“As one waters the creeper of devotion by hearing and chanting, the seed sprouts, and it gradually grows to penetrate the universal shell, rises beyond the Virāja River separating the spiritual and material world, passes even the Brahman effulgence, and enters eternal Vraja, where, by the continued watering of practicing devotional service, the fruit of pure love for Kṛṣṇa ripens.”
“However,” Mahāprabhu cautioned, “if the sādhaka offends a Vaiṣṇava while developing his bhakti in this world, that offense is compared to a mad elephant that destroys the creeper of devotion. So one must carefully protect one’s devotion with the fence of constant saintly association.”
Next, Mahāprabhu spoke on the danger of weeds in the form of ulterior desires that stunt the growth of the devotional creeper. He said that the varieties of these desires are countless and must be cut down diligently by the sādhaka. Pure love is the ultimate goal of life. To attain this, a devotee must cherish only the desire to serve Kṛṣṇa and should not worship demigods or men of this world. Pure devotion, Mahāprabhu described, is not covered by material knowledge or fruitive activities, is free of all material designations, is causeless and ceaseless, and is symptomized by constantly serving Kṛṣṇa for His pleasure. Mahāprabhu described the different stages of prema and the different rasas, or loving relationships with Kṛṣṇa, and the concurrent moods that develop based on one’s relationship with Kṛṣṇa. He then explained the supreme glory of mādhurya-rasa and Śrīmatī Rādhārānī’s love for Kṛṣṇa.
When instructing Rūpa Gosvāmī at Prayāga, Mahāprabhu said:
pārāpāra-śūnya gabhīra bhakti-rasa-sindhu tomāya cākhāite tāra kahi eka ‘bindu’
Caitanya-caritāmṛta, Madhya 19.137
[The ocean of bhakti-rasa is so vast that no one can estimate its length and breadth. However, just to help you taste it, I am describing but one drop.]
Rūpa Gosvāmī Prabhu took this drop of nectar from Mahāprabhu and composed the Bhakti-rasāmṛta-sindhu, therein elaborately describing the ocean of bhakti-rasa. He knew how to perfectly distribute this bhakti-rasa and he showed the method to everyone—sajātiyā āśraya snigdha sādhu-saṅga sato vare—one should always reside under the shelter of a sādhu who is more advanced than oneself and who is affectionate towards one. A sādhu tastes the transcendental rasa and has relationship with this rasa, thus, he can deliver it to others. Śrīla Rūpa Gosvāmī stored the treasure of Mahāprabhu’s teachings in scripture so that future generations would be able to open these and find the great wealth stored inside for them. He advised: stay in sādhu-saṅga while performing the limbs of bhakti. All your activities of bhakti must be in high-class association. Within sādhu-saṅga, Rūpa Gosvāmī described the highest limb of bhakti to be nāma-saṅkīrtana.
After ten days staying in Prayāga-rāja and teaching Śrīla Rūpa Gosvāmī, the Lord instructed Rūpa Gosvāmī to depart to Vṛndāvana. Rūpa Gosvāmī begged Mahāprabhu, “Prabhu, please let me stay with You; I cannot tolerate separation from You.”
Mahāprabhu smiled and embraced Rūpa Gosvāmī. “If you want to please Me,” He said, “than carry out My order and go to Vṛndāvana. Later, you can come and meet Me in Jagannātha Purī.”
Mahāprabhu told Rūpa Gosvāmī to go to Vṛndāvana, and discover the lost pastime places of Vṛndāvana. Mahāprabhu also instructed him to preach the bhakti-śāstras.