The Nectar of Devotion
The Complete Science of Bhakti-yoga
By His Divine Grace A.C. Bhaktivedanta Swami Prabhupada
The Nectar of Devotion is Srila Prabhupada's summary study of Bhakti-rasamrita-sindhu ("The Ocean of the Pure Nectar of Devotional Service") by Rupa Goswami, a direct disciple of Chaitanya Mahaprabhu.
Readers will find in The Nectar of Devotion many interesting and instructive pastimes of Krishna and His devotees, from a variety of Vedic scriptural sources, each meant to illustrate a particular aspect of rasa—relationship with Krishna—and to show how each manifests practically in one's life.
Srila Prabhupada specifically composed The Nectar of Devotion as an essential volume for practitioners of bhakti-yoga, Krishna consciousness. Part one consists of four "waves," the first being a general description of devotional service. The second concerns the regulative principles for executing devotional service, and the third wave, devotional service in ecstasy. In the fourth is the ultimate goal, love of God. The Nectar of Devotion explicitly describes all these topics along with their different symptoms.