I am a karma yogi, karma yoga teaches that act for the sake of karma, act without attachment. A karma yogi works because he likes to do the work and has no reason beyond it. A karma yogi does not renounce action, he simply renounces the fruit of action and becomes free from the miseries of action. His position is like a giver in this world and he never worries about getting anything. He knows that he is giving and does not ask for anything in return and that is why he does not fall in the clutches of sorrow. He knows that the bondage of sorrow is the result of the reaction of 'attachment'.
It has been said in the Gita that the equanimity of the mind is the yoga in which a person receives happiness and sorrow, profit and loss, victory and defeat, coincidence and separation in the mind with equal feelings. The performance of secular work by sacrificing the fruits of action also becomes like worship. No work of the world is separate from Brahman. Therefore, whatever be the nature of the work, selfless action is always devoted to God. The cause of rebirth is the accumulation of desires or unfulfilled desires. A karma yogi does not fall into the trap of the fruit of action, so there is no accumulation of desires. In this way a karma yogi also becomes free from the bondage of rebirth.