Later, Śrīla Rūpa Gosvāmī Prabhupāda elaborated the teachings of the Lord with profound knowledge of revealed scriptures and authoritative references from various Vedic literatures. Śrīla Śrīnivāsa Ācārya describes in his prayers to the six Gosvāmīs that they were all highly learned scholars, not only in Sanskrit but also in foreign languages such as Persian and Arabic. They very scrutinizingly studied all the Vedic scriptures in order to establish the cult of Caitanya Mahāprabhu on the authorized principles of Vedic knowledge. The present Kṛṣṇa consciousness movement is also based on the authority of Śrīla Rūpa Gosvāmī Prabhupāda. We are therefore generally known as rūpānugas, or followers in the footsteps of Śrīla Rūpa Gosvāmī Prabhupāda. It is only for our guidance that Śrīla Rūpa Gosvāmī prepared his book Bhakti-rasāmṛta-sindhu, which is now presented in the form of The Nectar of Devotion. Persons engaged in the Kṛṣṇa consciousness movement may take advantage of this great literature and be very solidly situated in Kṛṣṇa consciousness.
Bhakti means "devotional service." Every service has some attractive feature which drives the servitor progressively on and on. Every one of us within this world is perpetually engaged in some sort of service, and the impetus for such service is the pleasure we derive from it. Driven by affection for his wife and children, a family man works day and night. A philanthropist works in the same way for love of the greater family, and a nationalist for the cause of his country and countrymen. That force which drives the philanthropist, the householder and the nationalist is called rasa, or a kind of mellow (relationship) whose taste is very sweet. Bhakti-rasa is a mellow different from the ordinary rasa enjoyed by mundane workers. Mundane workers labor very hard day and night in order to relish a certain kind of rasa which is understood as sense gratification. The relish or taste of the mundane rasa does not long endure, and therefore mundane workers are always apt to change their position of enjoyment. A businessman is not satisfied by working the whole week; therefore, wanting a change for the weekend, he goes to a place where he tries to forget his business activities. Then, after the weekend is spent in forgetfulness, he again changes his position and resumes his actual business activities. Material engagement means accepting a particular status for some time and then changing it. This position of changing back and forth is technically known as bhoga-tyāga, which means a position of alternating sense enjoyment and renunciation. A living entity cannot steadily remain either in sense enjoyment or in renunciation. Change is going on perpetually, and we cannot be happy in either state, because of our eternal constitutional position. Sense gratification does not endure for long, and it is therefore called capala-sukha, or flickering happiness. For example, an ordinary family man who works very hard day and night and is successful in giving comforts to the members of his family thereby relishes a kind of mellow, but his whole advancement of material happiness immediately terminates along with his body as soon as his life is over. Death is therefore taken as the representative of God for the atheistic class of men. The devotee realizes the presence of God by devotional service, whereas the atheist realizes the presence of God in the shape of death. At death everything is finished, and one has to begin a new chapter of life in a new situation, perhaps higher or lower than the last one. In any field of activity—political, social, national or international—the result of our actions will be finished with the end of life. That is sure.