What metaphor does Chapter 47 use to explain the purifying power of saints, and what does it signify?

Chapter 47 employs a powerful metaphor involving the River Bhagirathi, also known as the Ganges, to illustrate the supreme purifying power of saints. The text explains that while the Ganges washes the sins of the world, she herself becomes soiled with these accumulated impurities. To cleanse herself, the holy river desires the dust from the feet of saints, knowing there is no other way to achieve deliverance from her own sins. As described in Chapter 47, this metaphor signifies that the spiritual power of a true saint like Sai Baba is so immense that even sacred entities, revered for their own purifying qualities, seek the saints' grace for their own purification, highlighting their elevated spiritual status.