What challenges did Das Ganu face when trying to translate the Ishavasya Upanishad, and how is the grace of a Guru essential for such tasks?

Das Ganu, though he started a verse-commentary on the Ishavasya Upanishad in simple Prakrit language, found that a word-for-word translation was unsatisfying. As detailed in Chapter 20, he couldn't grasp the "internal secret" or deep meaning on his own. The text explains that the Upanishads contain the essence of the Vedas and are very difficult to comprehend without the grace of God and a Guru. It's emphasized that even a great scholar cannot understand the hidden truth through their own efforts alone, as the path is difficult at every step without a Guru's guidance. For one attached to the Guru's feet, however, the hidden meaning opens up automatically.