The Sutra of the Heart of Transcendent Knowledge is also called, The Heart Sutra in short. “Heart” refers to the “essential instruction” or the “pith instruction” which encapsulates the essence of emptiness. The Heart Sutra is the Dharma Door of Practice of Guan Yin. Starting from contemplating on the dependent origination of emptiness, one could enter the ultimate reality. Furthermore, one could manifest great compassion and the bodhisattva spirit of liberating sentient beings. As Master Hsin Tao said, “The Heart Sutra is the practice of Chan and Guan Yin’s Method of Listening to Sound. The true Chan is the notionlessness in life. How do we work through life events with a heart that could remain undisturbed under external influences? It is to bring the mind back to where it should be. Let the mind be where it should be and take effect. Let the phenomena be where they should be and take effect.