The psychological condition of fear is divorced from any concrete and true immediate danger. It comes in many forms: unease, worry, anxiety, nervousness, tension, dread, phobia, and so on. This kind of psychological fear is always of something that might happen, not of something that is happening now. You are in the here and now, while your mind is in the future. This creates an anxiety gap. And if you are identified with your mind and have lost touch with the power and simplicity of the Now, that anxiety gap will be your constant companion. You can always cope with the present moment, but you cannot cope with something that is only a mind projection—you cannot cope with the future. Moreover, as long as you are identified with your mind, the ego runs your life, as I pointed out earlier. Because of its phantom nature, and despite elaborate defense mechanisms, the ego is very vulnerable and insecure, and it sees itself as constantly under threat. This, by the way, is the case even if the ego is outwardly very confident. Now remember that an emotion is the body's reaction to your mind. What message is the body receiving continuously from the ego, the false, mind-made self? Danger, I am under threat. And what is the emotion generated by this continuous message? Fear, of course.
— Eckhart Tolle