How does Chapter 48 differentiate between a Sadguru and other spiritual teachers who may have scriptural knowledge?

Chapter 48 draws a sharp distinction between a Sadguru and other teachers. It states that those who merely study the Vedas, practice breath control (Pranayama), or please audiences with talks about Brahman are not considered Sadgurus by the wise. The chapter criticizes teachers who possess vast verbal knowledge but lack self-experience, calling such knowledge "verbally hollow." The key differentiator highlighted in Chapter 48 is that a Sadguru can give direct, full experience, whereas a teacher who has no direct experience themselves has nothing of true substance to give to a disciple. The authority to enlighten comes only from this combination of knowledge and experience.