“The outer teacher is a messenger, the inner teacher the truth. 

If someone wants to reach you on the telephone, for example, they call your number. In the very same way, the buddhas call you through your buddha-nature, your inner teacher. He is the direct line, but until you know how to listen and hear, it is your outer teacher who answers the phone, They work through him, to you. It is important not to lose the sense of connection between the inner and outer teacher, The outer teacher is teaching you to yourself, and until you find the buddha in you. He is introducing you to yourself, and until you find the buddha within you, he is a substitute.”

Dzogchen Essentials: The Path That Clarifies Confusion