Awakened heart comes from being willing to face your state of mind. The sitting practice of meditation is a means to awaken this within you. When you awaken your heart, to your surprise, you find that it is empty. If you search for awakened heart, if you put your hand through your rib cage and feel for your heart, there is nothing there—except for tenderness. You feel sore and soft, and if you open your eyes to the world, you feel tremendous sadness. It is not the sadness of feeling sorry for yourself or feeling deprived. It is a natural situation of fullness. The genuine heart of sadness comes from this feeling that your nonexistent heart is full. Your experience is so raw, tender, and personal that even if a tiny mosquito lands on you, you feel its touch. 

-Chögyam Trungpa
from Shambhala: Sacred Path of the Warrior