Ishavasya Upanishad by Acharya Prashant  (Paperback, Acharya Prashant)

The Upanishads act as some kind of circuit-breakers. You live in your own contained world, and because the world is self-contained and self-ratified, therefore there is no way any element inside your world is ever going to disrupt your world or call it out as false. The Upanishads mischievously show you a contradiction, and now you are flabbergasted because one contradiction is enough to bring down your entire mental palace. A thousand things are not sufficient to verify the truth, but one exception is enough to nullify the truth. Is it not so? After all, what is the Truth? That which continues without interruption and without exception, right? That is the Truth. This is a ladder between two dimensions, and that’s the task of the Upanishad or the teacher. The world of the mind is being helped to meet the Transcendental.