Can you explain the reference to the Bhagavad Gita and the 'Avagraha' in the text? What is its significance?

Chapter 50 discusses a subtle interpretation of a verse from the Bhagavad Gita to highlight the importance of addressing ignorance. It specifically refers to the thirty-fourth verse of the fourth chapter, which begins 'Tadviddhi pranipatena...'. The text points out that in the third line of this verse, an 'Avagraha' (a Sanskrit grammatical symbol) appears before the word 'Jnana' (knowledge). This 'Avagraha' is interpreted as an indicator of 'Ajnana,' or ignorance. The significance is that it suggests one must first understand and confront ignorance before true knowledge can be properly instructed by the knowers of truth.