According to Chapter 26, what is the specific role of the Guru in a disciple's spiritual journey?

In the spiritual framework presented in Chapter 26, the Guru is paramount and indispensable for attaining enlightenment. The text explicitly states that in the entire world, only the Guru is capable of granting the knowledge of Truth to a disciple. The Guru's words, or 'Mahavakyas', are the key to dissolving the illusion of the world and revealing the light of non-dual bliss. The author's prayer to Sai Baba underscores this, asking Him to make this knowledge meaningful through direct personal experience, because without the Guru’s grace, spiritual understanding remains purely theoretical and ultimately fruitless.