Can you explain the two types of service a Sadguru accepts from devotees through books, as a way to foster their spiritual growth?

Chapter 0 outlines two distinct forms of service a Sadguru facilitates through literature to aid devotees. The first is when the Sadguru creates profound spiritual works themselves, such as the Shri Dnyaneshwari or Shri Dasbodh. The second method, which is equally significant, is when the Sadguru inspires devotees to write their biographies. The Sadguru then accepts service from both the writer and the wider community of followers who engage in the study and devotional reading (Parayans) of these biographical works. This process of studying a Guru's life story, like the Shri Sai Satcharita, serves as a powerful tool for devotees to connect with the Guru and fulfill their life's purpose.