How does Chapter 20 use the story of Das Ganu to explain the importance of a Guru in understanding complex scriptures like the Upanishads?

Chapter 20 powerfully illustrates the necessity of a Guru's grace through the predicament of Das Ganu. While attempting to write a commentary on the Ishavasya Upanishad, Das Ganu could translate the words but failed to grasp the 'internal secret,' leaving his mind without joy. This chapter explains that the Upanishads, being the essence of the Vedas, are incredibly difficult to comprehend without the grace of Hari and a Guru. It explicitly states that even a great scholar cannot uncover the hidden truth on their own, as the path is difficult at every step. However, for one devoted to the Guru's feet, the hidden meaning opens up automatically. Baba's instruction to Das Ganu—that a maidservant would resolve his doubt—underscores this principle, showing that true understanding comes from the Guru's will, not just intellect.