What is the meaning of Baba's story about the tortoise and how does it relate to giving mantras?

In Chapter 19, when asked for a secret mantra, Sai Baba uses an analogy of a mother tortoise to explain his own Guru's teaching method. He describes how a mother tortoise on one riverbank can nurture her young on the opposite bank simply with her loving gaze, without any physical contact or verbal instruction. This glance alone provides contentment and nourishment. Baba uses this to illustrate that his Guru never gave him a whispered mantra but instead protected and guided him with a merciful gaze. Therefore, Baba explains he cannot give a mantra he never received, advising the devotee to instead "pay attention to me," implying that grace is transmitted through focused devotion, not just verbal formulas.