How did Sai Baba's method of healing people evolve over time?

Initially, Sai Baba's approach to healing was quite direct and practical. According to Chapter 0, he used to give medicines to people and would never accept money for them. He was so compassionate that if a patient wasn't being cared for properly, he would personally go and tend to them himself. However, his methods changed later in his life. He stopped administering medicine and instead began giving only Udi, or sacred ash, which people found beneficial. He explained this transition by saying, "I used to give medicine to people before. Later, I stopped giving medicine and started saying 'Hari Hari', and while saying Hari Hari, I met Hari."