What was so special about the way Sai Baba spoke to Kaka Mahajani's friend? Why did it affect him so much?

The effect of Sai Baba's voice on Kaka Mahajani's friend was profound and pivotal, as described in Chapter 35. It wasn't just the words Baba spoke—"Why have you come in this manner?"—but the specific tone and vocal style. The friend was astonished because he recognized it as a perfect imitation of his deceased father's voice. The text notes he thought, "This is exactly my father's way of speaking; this voice is certainly familiar." Hearing this loving tone, as if from his own father's mouth, melted the friend's skepticism, causing him to forget his prior vow and bow down at Baba's feet.