A person in the intoxication of outer power that he possesses overlooks the cultivation or the development of inner power, and, depending upon the power that does not belong to him, one day becomes the victim of the very power that he holds. Because, when the outer power becomes greater and the inner smaller, the greater power eats up the inner power. So it is that the heroes, the kings, the emperors, the persons with great power of arms, wealth or outer influence, have become victims to the very power upon which they always depended. So one thinks, "If the outer power is not to be depended upon, then where is that power to be found upon which one can depend?" And that power is to be found in oneself. What power is it? In the terms of the Sufis that power is called Iman, conviction. And how is that power built?