Gyan yoga, also known as gyan marga, is the way of gaining true knowledge of the self. It is the art of union with the Divine, through pursuit of spiritual knowledge. A gyan yogi explores some very basic questions of life such as ‘who am I’ and ‘how am I related to the world as a whole’. Wisdom so gained helps him in getting freedom from the cycle of births and deaths.
Apart from gyan yoga, the other two paths prescribed in Bhagavad Gita are karma yoga and bhakti yoga. Though it is not possible to draw a clear-cut demarcation, but broadly speaking karma yoga and bhakti yoga are suitable for the men of action and men of emotion respectively ; and gyan yoga is pursued by the men of contemplation. One can choose the path of his spiritual freedom depending upon his interest, aptitude and inclination.
Gyan or the spiritual knowledge is not the the same thing as philosophical musings or scientific statements. Whereas the knowledge of any other discipline relates only to the subject matter of that particular branch of knowledge, the truth of spirit relates to whole of the existence. It is not the knowledge which is pursued for the sake of power and pelf ; but it is the wisdom the aim of which is to realise the ultimate truth.
Wisdom is not something which is to be acquired. It is inherent in the self. But it remains covered by avidya, the ignorance. The aim of gyan yoga is to pierce the veil of this ignorance. It is not soul but the mind which has to overcome the ignorance and let the wisdom of the soul be revealed. Once the ignorance is overcome, wisdom of the soul shines like a self-luminous source of light. When one experiences such wisdom, he is united with the Supreme.
While experiencing the mortal world, the immortal soul is deluded by the three modes of material nature. He is attracted by objects of the physical world and gets entangled in them. As a result, he forgets his essential nature. He forgets that he is an eternal fragment of the Supreme.
Gita has described in detail as to how one can understand the ultimate truth and also realise his essential nature, the self.
One must have firm determination and a clear goal, avoid bodily excesses of indulgence or abstinence, develop equanimity of mind, subdue all the senses ; and control the mind through constant practice and detachment. One must free himself from the clutches of fear, lust, anger and greed. One must be free from enmity to any of the creatures. One must regulate his breath and focus his mind on one point, to attain concentration of mind. One must do his prescribed duty without any attachment ; and without any expectation in return. One must dedicate all his actions to the Supreme Lord and receive the results with an attitude of glad acceptance. Full of love in his heart, one must worship Ishvara, the Supreme Lord with great devotion.
In this manner, he obtains liberating insights into the nature of his own self and also his relationship with the ultimate reality. The wisdom so gained by him is not only a theoretical knowledge but also an inward experience.
As a result, one understands that the body and the soul are distinct. Whereas the body, the mind and other objects of the physical world are transient, the self is indestructible and remains unchanged by the events of the material world. He then is freed from the good and evil influences of gunas, the three modes of material nature. As a result, the false ego gets dissolved and the embodied soul regains his pristine glory of perfect knowledge and pure consciousness. One realises the self and discovers the Supreme Self within.
Chapter 4 of Bhagavad Gita has given a detailed description of Gyan Yoga. It is stated that yagya for knowledge is superior than the one done for material gains because all works, without any exception, ultimately culminate, in wisdom (Shloka 4.33). The one who is full of faith, is sincere in his pursuit of wisdom ; and who has mastered his senses – such a person gains this wisdom and having obtained it, quickly he attains to the supreme peace (Shloka 4.39). After gaining this wisdom, one shall never be deluded again because such wisdom would enable him to see the entire creation in the self, and consequently in the Supreme Lord (Shloka 4.35). Nothing in this world is as purifying as this wisdom. The one who is perfected in yoga, he himself experiences that wisdom in his own self, in due course of time (Shloka 4.38).
Even if one is the most sinful of all sinners, still he can cross over the ocean of misery by this boat of wisdom (4.36).
To conclude, when one obtains equanimous wisdom, he is liberated from the bondage of works. He gains complete self-awareness. As a result, insight of the soul is born and the apparent ego merges with the divine consciousness. The soul is united again with the Supersoul. One then experiences the presence of the indwelling God. One becomes the master of his life.