Describe what specifically caused Kaka Mahajani's friend to abandon his vow and bow down to Sai Baba.

The transformation of Kaka Mahajani's friend is a key event in Chapter 35. He had firmly resolved not to bow his head to Sai Baba. However, this resolve was shattered by the 'magic power' in Baba's speech. When Baba spoke to him, the friend heard a perfect imitation of his deceased father's exact vocal style. Hearing these familiar words as if from his father's own mouth caused the friend to completely melt inside. Overcome with emotion and amazement, he entirely forgot his previous vow and spontaneously bowed his head at Sai Baba's feet.