Our Soul is our true and deepest teacherThe Bhagavad Gita is a yoga text, or scripture, that is a dialog between Lord Krishna and Arjuna. Some people believe that Lord Krishna was a Maha Avatar, physically present and guiding Arjuna. Some believe that Krishna was the spiritual consciousness within Arjuna, the teacher within him, his Soul, God’s presence within him.
John Friend's Anusara Invocation is referring to this "true teacher of the heart" that lies within us all. Here’s the Sanskrit for the chant, followed by the English interpretation:
Om Namah Shivaya Gurave
I bow to the true teacher of the heart
Whenever we receive guidance from our Soul Consciousness, the true teacher of the heart, I call it "heart guidance".