What are the main teachings in Chapter 48 of Sai Satcharitra regarding the definition of a true Sadguru?

Chapter 48 of the Shri Sai Satcharitra provides a detailed description of the characteristics of a true Sadguru, distinguishing them from other teachers. It explains that a Sadguru is not defined by their knowledge of Vedas or their ability to explain Vedanta, but by their possession of direct self-experience. As the chapter states, a true Sadguru is one who is a "giver of direct, full experience" and whose knowledge is not "verbally hollow." Furthermore, a Sadguru is free from egoism, views the disciple as Supreme Brahman with fatherly love, and is even willing to sacrifice their own body for the disciple's sake, never desiring service or livelihood in return.