What are the primary teachings and rules for devotees presented in Chapter 9 of the Sai Satcharitra?

Chapter 9 of the Sai Satcharitra conveys several key teachings for devotees. The most prominent rule, described as a unique characteristic of the Shirdi pilgrimage, is the absolute necessity of receiving Sai Baba's permission before departing. The chapter warns that leaving without his consent invites obstacles, but conversely, one should not linger after permission is granted, as that also brings trouble. Furthermore, the text explains the spiritual significance of Baba's practice of begging for food. It clarifies that this was not for himself but was a selfless act performed for the welfare of devotees, specifically for the removal of their 'Panchasuna' and other sins. Finally, the chapter impresses upon readers the profound truth that God, in the form of Sai, pervades all of existence.