Being lost in thoughts, thinking about things to do, what has been done, what could have been done… is not only tiring but also a brilliant way to waste energy.
It diminishes your peacefulness and clouds your clarity. Every time you become lost in thought it means exactly that – you are lost! To find yourself, allow your mind to become quiet, to become utterly tranquil. In the quiet depths of every being, there is a stillness that contains a deep inner peace and wisdom that can guide you in your life.
Source: Brahma Kumaris
Promise of Purity 