Gita 04.21 – Nirasha is not disappointment in fulfilling desire, but detachment from the fever to fu

Bg 4.21
nirasir yata-cittatma
tyakta-sarva-parigrahah
sariram kevalam karma
kurvan napnoti kilbisam

Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Such a man of understanding acts with mind and intelligence perfectly controlled, gives up all sense of proprietorship over his possessions and acts only for the bare necessities of life. Thus working, he is not affected by sinful reactions.

Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
A Krishna conscious person does not expect good or bad results in his activities. His mind and intelligence are fully controlled. He knows that because he is part and parcel of the Supreme, the part played by him, as a part and parcel of the whole, is not his own activity but is only being done through him by the Supreme. When the hand moves, it does not move out of its own accord, but by the endeavor of the whole body. A Krishna conscious person is always dovetailed with the supreme desire, for he has no desire for personal sense gratification. He moves exactly like a part of a machine. As a machine part requires oiling and cleaning for maintenance, so a Krishna conscious man maintains himself by his work just to remain fit for action in the transcendental loving service of the Lord. He is therefore immune to all the reactions of his endeavors. Like an animal, he has no proprietorship even over his own body. A cruel proprietor of an animal sometimes kills the animal in his possession, yet the animal does not protest. Nor does it have any real independence. A Krishna conscious person, fully engaged in self-realization, has very little time to falsely possess any material object. For maintaining body and soul, he does not require unfair means of accumulating money. He does not, therefore, become contaminated by such material sins. He is free from all reactions to his actions.

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