An action that outwardly seems to be bad and cruel need not necessarily be sinful. Acts that apparently cause pain to others may have to be committed for the good of the world and there is no sin in them.
Then what action is sinful and what is meritorious? The Lord answers this question also.
Only such deeds as are motivated by desire and hatred can be sin. Those performed for the well being of the world without being impelled by desire and hatred are meritorious even though they may seen to be cruel.
The question arises: Is there any action that does not spring from desire or hatred? I will give an example.
When a judge awards punishment to a man found guilty of crime is he driven by desire or hatred? His sentence may seem cruel but it is indeed for the Atmic well-being of the accused himself. If one's son is suffering from advanced insanity does one not keep him in chains? Is that sinful? It is for the son's good as well for the good of others who might come to harm by him.
When there is neither selfish desire nor hatred, there will be nothing unpleasant about any kind of work. One can then be always happy doing one's allotted work.
The reason for desire and hatred is ego-feeling, ahamkara. When there is no ego-sense, considerations of high and low, or inferior or superior, will be found meaningless. We will keep doing our work happily as a matter of duty and thus also contribute to the world's happiness.
The Karmayoga taught by the Gita is doing one's work without ahamkara, in a spirit of dedications to the Lord. This tradition of desireless action that purifies our inner being has existed in this land from the Vedic period. Sri Krsna Paramatman presents it to us as a boon encased in a handy casket.
If everybody acts with equal love for all and with a pure heart there will be neither any rivalry nor any quarrel in society. The world then will be filled with joy.
Sri Chandrasekharendra Saraswathi (1894 – 1994), the 68th pontiff of Kanchi Mutt 1894