The preface discusses different types of Guru service. How does it distinguish between worldly service and spiritual service, and what is considered the ultimate form of this practice?

In Chapter 0, the preface draws a clear distinction between worldly and spiritual Guru service. Worldly service, such as writing biographies of great politicians or historians, is described as limited by space and time, rooted in self-interest, and ultimately not yielding eternal spiritual fruits. In contrast, writing the biographies of saints is a form of spiritual service. However, the text proposes that the most certain and effective service for attaining salvation is to write the biography of one's own Sadguru, study it regularly, and perform recitations (Parayans and Saptahs) with unwavering faith and devotion. This is presented as the supreme form of written Guru service.