In the Vedas there are three processes for elevating one to the platform of spiritual consciousness. These processes are called karma, jnana and bhakti. Karma deals mainly with the field of ritualistic performances, and jnana deals with the field of speculative processes. In contrast, bhakti, the devotional service of the Lord, need have nothing to do with karma or jnana. Pure devotional service by definition is without any tinge of karma or jnana.
The goal of all auspicious activities - karma, jnana, yoga and bhakti - is the Supreme Personality of Godhead.
Generally, people are working to get some desired result for sense gratification. Everyone is working to get some money, and money is used to satisfy the senses. This is called karma. But, out of many millions of such karmis, or fruitive workers, one may become a jnani, or a man in knowledge. When a man becomes frustrated by working hard and tasting all the results of karma, and when he is still not satisfied, then he comes to the platform of knowledge.
Knowledge is characterized by inquiry - "Who am I? Why am I frustrated? Why am I confused? What is my real position?" That is the platform of knowledge. Out of many thousands of such persons who have attained to this platform of knowledge, one who has actually understood what is the position of the living entities is called liberated, brahma-bhuta. And out of many thousands of such liberated persons, hardly one can understand who is Krishna.
Pure devotional activities are of one variety only. And how these devotional activities can be coordinated with our daily, active life has been explained in Bhagavad-gita. Coordinating such devotional activities with our daily activities is technically known as karma-yoga. The same devotional activities when mixed with the culture of knowledge are technically called jnana-yoga. But when such devotional activities transcend the limits of all such work or mental knowledge, this state of affairs is called pure transcendental devotion, or bhakti-yoga.
Three paths are enunciated in the Gita: karma-yoga, jnana-yoga and bhakti-yoga. Those who are too addicted to fruitive activities are advised to perform actions which will bring them to bhakti. Those who are addicted to the frustration of empiric philosophy are also advised to act in such a way that they will realize bhakti. Karma-yoga is different from ordinary karma, and jnana-yoga is different from ordinary jnana. Ultimately, as stated by the Lord in the Bhagavad-gita, bhaktya mam abhijanati: only through execution of devotional service can one understand Krishna.
It therefore follows that the culmination of all yogas lies in bhakti-yoga, the rendering of devotional service unto Krishna. Actually, all of the yogas delineated in Bhagavad-gita end on this note, for Krishna is the ultimate destination of all the yoga systems. from the beginning of karma-yoga to the end of bhakti-yoga is a long way to self-realization. Karma-yoga, without fruitive results, is the beginning of this path. When karma-yoga increases in knowledge and renunciation, the stage is called jnana-yoga, or the yoga of knowledge. When jnana-yoga increases in meditation on the Supersoul by different physical processes, and the mind is on Him, it is called astanga-yoga. And, when one surpasses astanga-yoga and comes to worship the Supreme Personality of Godhead, Krishna, that is called bhakti-yoga, the culmination. Factually, bhakti-yoga is the ultimate goal, but to analyze bhakti-yoga minutely one has to understand the other processes. In the Chaitanya-caritamrita it is stated:
krishna-bhakti haya abhidheya-pradhana
"Devotional service to Krishna is the chief function of the living entity. There are different methods for the liberation of the conditioned soul - karma, jnana, and bhakti yoga - but all are dependent on bhakti."
The system of bhakti-yoga makes one eligible to enter Hari-dhama, the system of jnana-yoga makes one eligible to enter the impersonal Brahmajyoti, and the system of karma-yoga obliges one to remain in Devi-dhama and repeatedly be born and die, changing his material covering according to the standard of karma he performs. For those grossly engaged in identifying the body as the self, pious activity, or karma-yoga, is recommended. For those who identify the mind with the self, philosophical speculation, or jnana-yoga, is recommended. But devotees standing on the spiritual platform have no need of such material conceptions of adulterated devotion. By karma-yoga we attempt to get out of the gross body, and by jnana-yoga we attempt to get out of the subtle body, but by bhakti-yoga we can directly transcend both the subtle body (mind, intelligence and ego) and the gross material body.
For any idea, program, plan or device, there is first of all the contemplation of the plan, and that is called bija, or the seed. The methods, rules and regulations by which one is perfectly trained in devotional service constitute the bhakti-lata-bija, or seed of devotional service. This bhakti-lata-bija is received from the spiritual master by the grace of Krishna. Other seeds are called anyabhilasa-bija, karma-bija and jnana-bija. If one is not fortunate enough to receive the bhakti-lata-bija from the spiritual master, he instead cultivates the seeds of karma-bija, jnana-bija, or political and social or philanthropic bija. However, bhakti-lata-bija is different from these other bijas. Bhakti-lata-bija can be received only through the mercy of the spiritual master. Therefore one has to satisfy the spiritual master to get bhakti-lata-bija (yasya prasadad bhagavat-prasadah). Bhakti-lata-bija is the origin of devotional service. Unless one satisfies the spiritual master, he gets the bija, or root cause, of karma, jnana and yoga without the benefit of devotional service. However, one who is faithful to his spiritual master gets the bhakti-lata-bija. This bhakti-lata-bija is received when one is initiated by the bona fide spiritual master.
By karma-misra-bhakti (bhakti mixed with fruitive inclination) one is elevated to the celestial kingdom, by jnana-misra-bhakti (bhakti mixed with mental speculation) one is able to merge in the Brahman effulgence, and by yoga-misra-bhakti (bhakti mixed with the desire for mystic perfections) one is able to realize the omnipotency of the Supreme Personality of Godhead. But pure bhakti does not depend on karma, jnana or yoga, for it simply consists of loving affairs. The liberation of the bhakta, therefore, which is called not just mukti but vimukti, surpasses the five other kinds of liberation - sayujya, sarupya, salokya, sarsti and samipya. A pure devotee always engages in pure service (anukulyena krishnanu silanam bhaktir uttama). Taking birth in the upper planetary system as a demigod is a chance to become a further purified devotee and go back home, back to Godhead. Ultimately there is only one way to attain the true liberation known as vimukti, and that is by satisfying the Supreme Personality of Godhead.
jnana-karma-yoga-dharme nahe krishna vasa
krishna-vasa-hetu eka - prema-bhakti-rasa
"By following the Paths of speculative philosophical knowledge, fruitive activity or mystic yoga to control the senses, one cannot satisfy Krishna, the Supreme Lord. Unalloyed devotional love for Krishna is the only cause for the Lord's satisfaction."
Krishna is only interested in one's devotion. As such He is not attracted by karmis, jnanis or yogis. Therefore Krishna advises in the Bhagavad-gita for everyone to take to bhakti and attain instant peace from the material world:
bhoktaram yajna tapasam
suhridam sarva bhutanam
jnatva mam shantim ricchati
"A person in full consciousness of Me, knowing Me to be the ultimate beneficiary of all sacrifices and austerities, the Supreme Lord of all the planets and demigods, and the benefactor and well-wisher of all living entities, attains peace from the pangs of material miseries."
Why such a person attains peace from all miseries? If one understands bhotaaram yajna tapasaam, that Krishna is the supreme enjoyer of everything, then naturally one will not try to enjoy the fruits of his work. Hence one will not attempt to be a karmi. If one understands sarva-loka maheshvaram, that the Lord is the supreme proprietor of everything, one will not foolishly think he himself could become the supreme proprietor, Absolute Truth. Hence he would never attempt to be a jnani. And if one knows suhridam sarva bhutaanaam, that the Lord is the supreme well-wisher of all living entities, then naturally one will not try to take the post of well-wishing friend by displaying some cheap siddhis to the ignorant. As such, one will not attempt to become a yogi. Thus one who knows Krishna, as explained by Krishna Himself in the Bhagavad-gita, will surrender to Krishna in full devotion, bhakti, and give up all futile endeavours for karma, jnana, and yoga.
With Thanks from: http://www.indiadivine.org