Gita 4.36
api ced asi papebhyah
sarvebhyah papa-krttamah
sarvam jnana-plavenaiva
vrjinam santarisyasi
Meaning
Even if you are the most sinful of all sinners, you shall undoubtedly, cross all sins by the boat of knowledge (wisdom), alone.
Explanation
Lord Krishna completes the discourse on jnana by extolling the glory of it. To emphasise the power of spiritual knowledge He specifically states in this verse that even the most incorrigible sinner is redeemed if changing their ways acquires and applies spiritual knowledge in their consciousness.
Generally sinners are not engaged in spiritual practice, but it does not mean that they cannot be engaged in it. If by coming into contact, with a great soul or by being influenced by an incident or circumstance or environment etc., they resolve, that they have to gain knowledge of the self, or God, they cross the ocean of sins, by the boat of knowledge, of the self.
Gita 4.37
yathaidhamsi samiddho ‘gnir
bhasmasat kurute ‘rjuna
jnanagnih sarva-karmani
bhasmasat kurute tatha
Meaning
As blazing fires burn firewood to ashes, O Arjuna, so does the fire of knowledge, reduce all actions to ashes.
Explanation
One might wonder that just as crossing the ocean by boat does not destroy the ocean how is it that the boat of spiritual knowledge can destroy all one’s sins. Lord Krishna states here that the boat of spiritual knowledge will destroy all reactions to actions both those leading to merit and those leading to demerit.
As blazing fire reduces fuel to ashes, so does the fire of knowledge, reduce the three kinds of actions (i.e.,)-prarabdha (in the form of fate), sancita (accumulated actions) and Kriyamana (the present actions), to ashes. It means that when a man gains knowledge of the self, his affinity for the actions or the world is totally renounced. Consequently, the world loses its independent existence and there remains, only God.
Gita 4.38
na hi jnanena sadrsam
pavitram iha vidyate
tat svayam yoga-samsiddhah
kalenatmani vindati
Meaning
In this world, there is nothing as sublime and pure as transcendental knowledge. Such knowledge is the mature fruit of all mysticism. And one who has achieved this enjoys the self within himself in due course of time.
Explanation
In this world nothing is as purifying as spiritual knowledge. Then why is not everyone pursuing this? Lord Krishna explains that first one must become qualified from prolonged practice of karma yoga or prescribed Vedic activities performed without desire for rewards. Then in due course of time, if there is no interruption, knowledge will arise leading to purity of heart after which soul realisation will be achieved.
This knowledge of the self cannot be gained by the senses, mind, intellect and other means (instruments). One will find the knowledge of the self, in himself. The means such as, listening to Vedanta texts, cognition and constant and deep meditations etc., may help in removing the obstacles such as notion of impossibility of gaining knowledge and contrary sentiments etc., but they cannot induce a man, to – gain the knowledge of self. He can gain that knowledge, by renouncing his affinity for the insentient. As the world can be seen with an eye but an eye cannot be seen by itself, but it can be said, that the organ with which any object is seen is the eye. So it can be said, that He who is the Knower of all persons and objects etc., and by Whom all objects etc., are known, is the self or God, Who is not known by any means.
Gita 4.39
sraddhaval labhate jnanam
tat-parah samyatendriyah
jnanam labdhva param santim
acirenadhigacchati
Meaning
He who has faith and is devoted and who controls his senses, gains knowledge (wisdom) and having gained knowledge he achieves the Supreme peace in no time.
Explanation
A person may acquire knowledge by themselves but here are presented all the qualities that are essential for such a person to succeed. The word sraddhavan means a person who has faith. Faith means firmly believing. The person with faith who follows the Vedic instructions of the spiritual master and who wholeheartedly believes in the knowledge of the Vedic scriptures and who is self-controlled; only such a person receives spiritual realisation and none other. Therefore before one receives spiritual knowledge through the auspices of faith one has to undergo the path of karma yoga or performance of prescribed Vedic activities for one’s purification. After spiritual realisation is attained then one has become liberated and has no need to perform any action.
In Karma yoga and Jnana yoga there is predominance of discrimination and in Bhakti yoga there is predominance of belief-faith. At first the Self-realization is attainable-this faith a seeker must have, then only he will strive for it.