Based on Chapter 17, what is the role of the Guru, and why is mere knowledge sometimes insufficient for finding peace?

Chapter 17 highlights the indispensable role of the Guru in spiritual attainment. It states that the Guru can show the path to a place that is beyond the reach of the sun's rays, the intellect, and even the Vedas. This implies the Guru guides one through realms inaccessible by ordinary means. The chapter also explains why knowledge alone can be insufficient. It questions the benefit of a person being 'learned' if they are constantly engaged in sinful deeds and cannot distinguish right from wrong. Similarly, it points out that someone who is always restless, whose heart is unsatisfied, and whose mind is distracted by the greed of the senses, will not find peace even with knowledge.