The only power for the mystic is the power of love.
Every kind of power lies in this one thing which we call by the simple name: love. Charity, generosity, kindness, affection, endurance, tolerance, and patience--all these words are different aspects of one; they are different names of only one thing: love. Whether it is said, 'God is love,' or whatever name is given to it, all the names are the names of God; and yet every form of love, every name for love, has its own peculiar scope, has a peculiarity of its own. Love as kindness is one thing, love as tolerance is another, love as generosity is another, love as patience another; and yet, from beginning to end, it is just love.
Remember therefore that for higher attainment on the spiritual path, study is secondary; all knowledge of occult and psychic law, all magical powers, are secondary. The first and most important principle is the cultivation of the heart quality.
One may ask: How to cultivate the heart quality? There is only one way: to become selfless at each step one takes forward on this path, for what prevents one from cultivating the loving quality is the thought of self. The more we think of our self the less we think of others, and as we go further the self grows to become worse and worse. In the end the self meets us as a giant which we had always fought; and now at the end of the journey the giant is the stronger. But if from the first step we take on the path of perfection we struggled and fought and conquered this giant which is the self, it could be done only by the increasing power of love.
What do I mean by love? It is such a word that one cannot give one meaning. All attributes like kindness, gentleness, goodness, humbleness, mildness, fineness, are names of one and the same thing. Love therefore is that stream which when it rises, (it also) falls in the form of a fountain, and each stream coming down is a virtue. All virtues taught by books or by a religious person have no strength or life because they have been learned; a virtue that is learned has no power, no life. The virtue that naturally springs from the depth of the heart, the virtue that rises from the love-spring and then falls as many different attributes, that virtue is real. There is a Hindustani saying, 'No matter how much wealth you have, if you do not have the treasure of virtue, it is of no use'. The true riches is the ever increasing spring of love from which all virtues come.
--Hazrat Inayat Khan from "The Bowl of Saki"