How do the concepts of 'Nishtha' (Faith) and 'Saburi' (Patience) relate to the Guru-disciple relationship in Sai Baba's philosophy?

In Sai Baba's philosophy, 'Nishtha' (Faith) and 'Saburi' (Patience) are the cornerstones of the Guru-disciple relationship. Chapter 19 explains that even a very powerful Guru primarily expects 'strong faith at the Guru’s feet and the strength of courage which is patience' from a disciple. These two qualities are the true price of discipleship. The text uses an analogy, comparing a disciple to a gem that, when polished with faith and patience, becomes a brilliant jewel, unlike a stone which remains a stone. The narrator's twelve years of devoted service, gazing at the Guru's face without hunger or thirst, exemplifies this deep-rooted faith and patience, which in turn earns the Guru's constant protection and immense love.