Can you explain the analogy of the mother tortoise that Baba uses in his teachings?

In Chapter 19, Sai Baba uses the analogy of a mother tortoise to explain the nature of a Guru's grace. He describes how a mother tortoise, standing on one bank of a river, can nourish and protect her young on the opposite bank simply through her loving gaze. No physical contact or verbal communication is needed. Baba uses this powerful image to illustrate how his own Guru cared for him from afar, protecting him with a 'merciful glance.' He then applies this to his own teaching method, explaining to a devotee that just as the tortoise's young are content with her gaze alone, a disciple can receive spiritual wealth simply by focusing their loving attention on the Guru, making a formal, spoken 'upadesh' or mantra unnecessary.