How does Chapter 47 use the analogy of the River Ganges to illustrate the power of saints?

Chapter 47 employs a powerful analogy using the River Bhagirathi, or Ganges, to emphasize the purifying power of saints. The text explains that as the Ganges washes away the sins of the world, she becomes soiled herself with these accumulated impurities. To wash away her own 'sins' and find deliverance, the river herself desires the dust from the feet of saints, wondering when they will come to bathe within her. As presented in Chapter 47, this metaphor powerfully conveys that the holiness of saints like Sai is so immense that even a sacred entity like the Ganges seeks their grace for its own purification.