The preface is by Balkrishna Vishwanath Dev. What biographical information does the book give about him and his relationship with Sai Baba?

The source text identifies the author of the preface as Late Balkrishna Vishwanath Dev, but it provides no further biographical details about his life, his background, or his specific relationship with Sai Baba. The preface, as detailed in Chapter 0, focuses on his philosophical and devotional views. He elaborates on the ancient principle of needing a Sadguru for salvation, the different types of Guru service, and his belief that the highest form of service is to write the biography of one's Sadguru and encourage its regular study.