"People pursue spirituality with their brain: that is where they are mistaken. Spirituality is attained through the heart. What do I mean by the heart? Is it the nervous center in the midst of the breast, the small piece of flesh that doctors call the heart? No, the definition of the heart is that it is the depth of the mind, the mind being the surface of the heart. That in us which feels is the heart, that which thinks is the mind. It is the same thing which thinks and feels, but the direction is different: feeling comes from the depth, thought from the surface. … The Sufis have therefore considered the development of the heart quality as a spiritual culture, and have called it the culture of the heart. It consists of the tuning of the heart.
Tuning means changing the pitch of the vibrations. Tuning the heart means changing the vibrations, bringing them to a certain pitch which is the natural one where you feel the joy and ecstasy of life, which enables you to give pleasure to others even by your presence because you are tuned. When an instrument is properly tuned you need not play music on it; just by striking it you will feel a great magnetism coming from it. If an instrument well-tuned can have that magnetism, how much greater should be the magnetism of hearts that are tuned. Rumi says, ‘Whether you have loved a human being or whether you have loved God, if you have loved enough you will be brought in the end into the presence of the supreme Love itself’."
Hazrat Inayat Khan (1882-1927)