According to the teachings in Chapter 10, what is the role of a Sadguru like Sai Baba in a devotee's life, especially concerning destiny and karma?

Chapter 10 profoundly illustrates the transformative power of a Sadguru in a devotee's spiritual and worldly life. The text states that by placing pure faith in the Guru's feet, He can 'strike a nail over the lines of destiny,' signifying his ability to alter a person's fate. The chapter further explains that serving the Sadguru destroys the cycle of worldly existence (Samsara) and helps devotees overcome the three types of misery. By the Guru's mere sight, as mentioned in Chapter 10, the knots of the heart are broken, attachments vanish, and both accumulated and current karmas are destroyed, leading the devotee effortlessly towards liberation.