What was the nature of Shri Sai Baba's spoken teachings? Did he deliver complex philosophical lectures?

The source material from Chapter 0 clarifies that Shri Sai Baba did not openly explain profound Vedanta subjects or give formal discourses on the Upanishads. His advice was described as being primarily ethical. The text explains this method by noting that a Sadguru's practice is to first purify the disciple's mind and heart before implanting higher knowledge, a practice Maharaj followed. Therefore, his teachings focused on general ethical principles. As Chapter 0 mentions, this practical advice was considered even more valuable because of the experiential benefits it brought to the devotees who approached him with faith.