What is the meaning of the comparison to the River Ganges in Chapter 47? Why would it need to be purified?

Chapter 47 uses a powerful metaphor involving the River Bhagirathi, or Ganges, to illustrate the supreme purifying power of saints like Sai Baba. The text explains that the Ganges, by washing the sins of the world, becomes soiled herself with accumulated impurities. To cleanse herself, the river desires the dust from the feet of saints, knowing that without this contact, there is no deliverance from her own burden of sins. This imagery emphasizes that the holiness of saints is so profound that even a sacred entity like the Ganges seeks their grace for purification.