IT IS ONLY WHEN THE MIND IS VERY CALM AND COLLECTED THAT THE WHOLE OF ITS ENERGY IS SPENT IN DOING GOOD WORK.

 I have been asked many times how we can work if we do not have the passion which we generally feel for work. I also thought in that way years ago, but as I am growing older, getting more experience, I find it is not true. The less passion there is, the better we work. The calmer we are, ...the better for us, and the more the amount of work we can do. When we let loose our feelings, we waste so much energy, shatter our nerves, disturb our minds, and accomplish very little work. The energy which ought to have gone out as work is spent as mere feeling, which counts for nothing. It is only when the mind is very calm and collected that the whole of its energy is spent in doing good work.

- Swami Vivekananda
The Complete Works of Swami Vivekananda/Volume 2/Practical Vedanta and other lectures/Practical Vedanta: Part I (Delivered in London, 10th November 1896)