Bhagwad Gita - Post 57

Yathaidhaamsi samiddho’gnir

Bhasmasaat kurute’rjuna;

Jnaanaagnih sarvakarmaani

Bhasmasaat kurute tathaa.

As the blazing fire reduces fuel to ashes, O Arjuna, so does the fire of knowledge reduce all actions to ashes!

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 actions / effects or consequences of one’s actions. 

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.

Swami Chinmayananda says,

"Whatever be the quality, shape, condition, color, etc., of the fuel pieces, when all of them are taken to the fire-place and digested by the fire, they become one homogeneous mass of ash! In the samples of ash left in the hearth, we cannot recognize the ash of a particular twig as different from that of another. 

Similarly, all Karmas, it is said, good, bad, or indifferent, get burnt up in the 'Fire of Knowledge' and will become something altogether different from what they were in their cause-and-effect condition. 

Solid fuel having girth, weight, smell, etc., becomes almost weightless, with no specific color except a light-greyness, when it comes to the final state of ash.

Actions leave reactions. The reactions mature at different periods of time depending upon the quality and intensity of the actions. 

From beginning less time, in our different manifestations, we have been, at every moment, acting in our ego-centric vanity and individuality. All those actions must have left their residual impressions and they have to be lived through.

This entire Karma has been scientifically considered as falling under three classifications. They are called "not yet operative" (Sanchita), "operative" (Prarabdha), and "to be operative in future" (Agami). When, in the Geeta, it is said that all Karmas are burnt down, the Lord means the entire Sanchita and Agami."

Sanchita , Prarabdha and Agami karmas have been dealt in great detail in posts under “KARMA” theme.

So, as explained above, sanchita  karmas are burnt / become ineffective like roasted seeds which cannot bear / bring forth plant / tree.

Agami karma in any way will not fetch any fresh karma as such actions are not taken up with the coloring of Ego.  

Still, even a sage has to undergo prarabdha karma, those karmas for which results have already started. 

But in his fire of knowledge, he is aware that the prarabdha karma is being cleared by the jiva in him whereas in reality, he is aware that he is not that Jiva but  the very Atman. 

Hence, those prarabdha karmas do not affect his state of existence.

When Sri Rama Krishna was suffering from acute pain due to cancer, one day, his nephew walks up to thakur and asks, "Master, I see you are having lot of pain, but I am also seeing you in joy".

Thakur smiles and replies, " The rascal you caught me".

He meant, yes, you are knowing that the physical pain is not affecting the eternal state of Joy / Bliss of Ramakrishna.

Love.

PS- Readers are requested to go through the necessary posts under “karma” theme for more clarity on Sanchita, Prarabdha and Agami Karma.