Moksa Opadesa Yoga: Bhagavad Gita Chapter 18 [Final Revelations of the Ultimate Truth]
Krishna Said > Shaloka: 9
But he who performs his prescribed duty only because it ought to be done, and renounces all attachment to the fruit–his renunciation is of the nature of goodness, O Arjuna.
Prescribed duties must be performed with this mentality. One should act without attachment for the result; he should be disassociated from the modes of work. A man working in Krishna consciousness in a factory does not associate himself with the work of the factory, nor with the workers of the factory. He simply works for Krishna. And when he gives up the result for Krishna, he is acting transcendentally.