Why was Das Ganu struggling with his commentary on the Ishavasya Upanishad, and what does Chapter 20 reveal about this challenge?

Das Ganu's struggle, as detailed in Chapter 20, stemmed from his inability to access the deeper meaning of the Ishavasya Upanishad for his commentary. Although he was translating it into simple Prakrit language, he couldn't penetrate its "internal secret," which left him unsatisfied. The chapter uses his predicament to illustrate a broader spiritual principle: understanding sacred texts is not merely an intellectual exercise. It explains that the Upanishads are the "treasure" of the Vedas and are very difficult to grasp without the Guru's grace. The text suggests that scholarly effort alone is insufficient, as the hidden truth is a path that is "difficult at every step" without a guide to reveal it.