Swami Vivekananda advises in Karma Yoga: The Yoga of Action,

If working like slaves results in selfishness and attachment, working as master of our own mind gives rise to the bliss of non-attachment. We often talk of right and justice, but we find that in the world right and justice are mere baby’s talk. There are two things which guide the conduct of men: might and mercy. The exercise of might is invariably the exercise of selfishness. All men and women try to make the most of whatever power or advantage they have. Mercy is heaven itself; to be good, we have all to be merciful. Even justice and right should stand on mercy. All thought of obtaining return for the work we do hinders our spiritual progress; nay, in the end it brings misery.