What does the preface of the Shri Sai Satcharita say about the teachings of a specific saint, like Meera Bai?

The provided text from the preface of the Shri Sai Satcharita does not contain any specific information about Meera Bai or her teachings. Instead, Chapter 0 establishes a general and ancient principle that salvation is unattainable without the grace of a Sadguru. The author explains that a Sadguru can manifest in many forms, including saints, deities, family members, or even a book. The focus is on the universal importance of having and serving a Guru, rather than providing a list or details of individual saints.