Based on Chapter 16, why did Sai Baba take a human form and what 'weapon' does he use against worldly existence?

Chapter 16 explains that the Sadguru, the "King of Yogis," has taken a physical body for a compassionate purpose: "for the sake of helping others, to uplift the poor and lowly." It was an act undertaken to guide humanity. The primary tool he employs to combat the illusion of worldly life is described metaphorically as the "sharp blade of the sword of Knowledge." As Chapter 16 vividly portrays, the mere sight of His hand raised to strike with this sword causes the "tree of worldly existence" to tremble in fear, signifying that the Guru's wisdom has the power to sever the roots of ignorance and attachment.