Bhakti, or devotional service, is characterized by vairagya and jnana. Jnana refers to understanding that one is not his body, and vairagya means disinterest in sense gratification. These two primary principles of separation from material bondage can be realized on the strength of bhakti-yoga. Thus when a devotee is fixed in the loving service of the lotus feet of the Lord, he will never come back to this material existence after quitting his body, as confirmed in Bhagavad-gita by the Lord (tyaktva deham punar janma naiti mam eti so rjuna [Bg. 4.9]).

In this verse the word vijnana is specifically important. Jnana, the knowledge of spiritual identity that one attains when he does not consider himself to be the body, is explained in Bhagavad-gita as brahma-bhuta, the revival of spiritual realization. In the conditioned state of material existence one cannot be spiritually realized because he identifies himself materially. The understanding of the distinction between material existence and spiritual existence is called jnana. After coming to the platform of jnana, or the brahma-bhuta state, one ultimately comes to devotional service, in which he completely understands his own position and the position of the Supreme Personality of Godhead. This understanding is explained here as vijnana-visesa. The Lord says, therefore, that knowledge of Him is vijnana, science. In other words, when one is strengthened by scientific knowledge of the Supreme Personality of Godhead, his position of liberation is guaranteed. In Bhagavad-gita (9.2), the science of devotional service is described as pratyaksavagamam dharmyam, direct understanding of the principles of religion by realization.

By practicing bhakti-yoga, one can directly perceive his advancement in spiritual life. In other practiceslike karma-yoga, jnana-yoga and dhyana-yogaone may not be confident about his progress, but in bhakti-yoga one can become directly aware of his progress in spiritual life, just as a person who eats can understand that his hunger is satisfied. Our false appetite for enjoyment and lordship of the material world is due to a prominence of passion and ignorance. By bhakti-yoga these two qualities are diminished, and one becomes situated in the mode of goodness. Gradually surpassing the mode of goodness, one is situated in pure goodness, which is not contaminated by the material qualities. When thus situated, a devotee no longer has any doubts; he knows that he will not come back to this material world.