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

As described in Chapter 26 of the Shri Sai Satcharitra, the Guru's role is absolutely essential for spiritual realization. The text asserts that in the entire world, only the Guru is capable of granting the knowledge of Truth to a disciple, which is necessary to see past the illusion of Maya. The author prays to the Sadguru, Sai Baba, to help him discriminate between the eternal and the temporary and to turn his intellect inward. It is through the "Great Sayings (Mahavakyas) of the Sadguru," as mentioned in Chapter 26, that the light of non-dual bliss can shine forth, allowing the disciple to overcome false logic and achieve true understanding.