The fire of knowledge burns all karma; Krishna consciousness alone liberates the soul from material bondage.Listen — Srila Prabhupada Uvaca
Prabhupāda: yathaidhāṃsi samiddho 'gnir bhasmasāt kurute 'rjuna jñānāgniḥ sarva-karmāṇi bhasmasāt kurute tathā [Bg 4.37] [As the blazing fire turns firewood to ashes, O Arjuna, so does the fire of knowledge burn to ashes all reactions to material activities.] Yathā, "as," as an edhāṃsi. Edhāṃsi means "fuel." Sammidho 'gniḥ, "blazing fire"; bhasmasāt, "turns into ashes." Just like blazing fire, whatever you put into it, any fuel, that becomes turned into ashes, similarly, jñānāgniḥ, "when your fire of knowledge will be ablazed, then sarva-karmāṇi, all reaction of your work, will turned into ashes." Because the reaction of our karma, reaction of our work, is the cause of our bondage. There are good work and bad work. Here it is stated, sarva-karmāṇi.
Sarva-karmāṇi means either good work or bad work. There are reaction of bad work, and there is reaction of good work. But a, a person who is going to be liberated from this material bondage, for him, both good work and bad work are reprehensible. There is no need of reaction of good work also. In this material world we are attached to perform good work.
Not all. Those who are in the modes of goodness, they want to do some good work in the material estimation. And those who are in the modes of passion and ignorance, they do work, bad work, passionate work, work in ignorance. But those who are going to be Kṛṣṇa conscious, they have no need, either this good work or bad work. Why?
Now, either you enjoy the reaction of good work or bad work, your material bondage is there. Suppose by bad work I am born... Because, according to work, there are different position of life. Janmaiśvarya-śruta-śrībhir edhamāna-madaḥ pumān [SB 1.8.26]. [My Lord, Your Lordship can easily be approached, but only by those who are materially exhausted, because one who is on the path of [material] progress, trying to improve himself with respectable parentage, great opulence, high education and bodily beauty, cannot address You with sincere feeling.] By good work we get good heritage, birth in a very good place, in a high family, in rich family, aristocratic family.
And with bad work we may get our birth even in the animal kingdom or lower-graded family, poor family. These are Vedic estimation of good work and bad work. But for a person who is going to be Kṛṣṇa conscious, he has no need either for good work or bad work, because he has no need of bondage again. Suppose I am born in a very aristocratic family, very rich family. That does not mean that I am getting free from the material miseries.
Just like we are sitting here. Some of you are very well situated. Some of you coming from rich family and some of you may not be so rich—from middle-class family. But the temperature of this day is equally heating us.
There is no consideration that "Here is a person who is coming from rich family, so the temperature should be lesser for him." No. Therefore, either we enjoy the reaction of good work, either we enjoy the reaction of bad work, we have to accept this material body. And as soon as we accept this material body, we have to undergo the material miseries. But our whole program is... Duḥkhālayam aśāśvatam.