According to the preface, who benefits when a devotee studies and performs Parayans of a Guru's biography?

Chapter 0 explains that multiple people benefit from the study of a Guru's biography. Primarily, the devotees who study and perform Parayans of the work are said to achieve the purpose of their lives. At the same time, the writer of the biography also benefits. By others studying the work, the author is credited with gaining the merit of serving God in humanity (Jan-Janardan) and performing public service. This is in addition to the service they already performed for their Guru by creating the detailed poetic biography in the first place.