Can you explain the philosophical idea of Sai being both formless and with form as mentioned in this chapter?

Chapter 30 touches upon a deep philosophical concept regarding Sai Baba's nature. The text explains that in the beginning, He resides as the formless, or 'Nirguni.' However, through the power and qualities of his devotees' devotion, He is drawn from this formless state into a form with attributes, known as 'Saguni.' This transition is not a change in His essential nature but rather a manifestation for the sake of His followers. As described in Chapter 30, this illustrates how the devotee's faith and love can make the abstract, formless divine accessible and tangible, positioning Sai as the 'crest-jewel among saints' who embodies this principle.