How do we decide who is an emanation of whom? It is not based on inference or feeling. There is no way our five senses can see such a hidden connection. Neither can our logic infer such results. We can only rely on the prophecy of Padmasambhava and the vajra speech of great masters. We can fully trust in the practice and character of these great masters who would never deceive sentient beings. The words spoken by the Buddha and these noble beings who were like buddhas, are called authoritative scriptures.
[Excerpt from Luminous Wisdom Book Series ~ The Guru Yoga Practice of the Seven-Line Prayer to Padmasambhava]