In what two ways does a Sadguru accept service from devotees through books and literature?

According to the preface in Chapter 0, a Sadguru accepts service from devotees through literary works in two distinct manners. The first is when the Sadguru themselves authors profound spiritual texts, such as the Shri Dnyaneshwari or Shri Dasbodh. The second way is by inspiring their devotees to write their biographies. In this scenario, the Sadguru accepts service not only from the writer but also from the entire congregation of devotees who engage with the biography through dedicated study and devotional readings known as Parayans. This creates a cycle of service and spiritual merit.