According to the account in the sacred texts, what are the three essential actions for a disciple to gain knowledge from a Guru?

Based on the dialogue between Sai Baba and Nana Chandorkar in Chapter 39, Nana explains the traditional path to knowledge as described in a key Gita verse. He outlines three essential actions for a disciple. The first is prostrating at the Guru's feet (pranipatena), signifying complete surrender and humility. The second is serving the Guru with one's life (sevaya), which demonstrates devotion and commitment. The third is asking respectful questions (pariprashnena) to clarify doubts and deepen understanding. Nana's explanation confirms that by performing these actions, the wise Gurus, who have realized the Truth, will then instruct the disciple in true Knowledge.