I've heard some people consider figures like Jesus Christ as Sadgurus. Is there any mention of Jesus in the preface of the Sai Satcharita?

The preface of the Shri Sai Satcharita does not mention Jesus Christ or any other figures from non-Indian traditions by name. The text, found in Chapter 0, speaks in general principles. It establishes a 'firm belief' in the necessity of a Sadguru for salvation and notes that this Guru can belong to 'any caste, religion, age.' While this principle is broad, the preface itself does not apply it to specific non-Vedic figures. Instead, it references Lord Dnyaneshwar Maharaj's commentary on the Shrimad Bhagavad Gita to describe how one should serve a Guru to attain knowledge and dispel doubts.