Can you explain the analogy about the River Ganges that is presented in Chapter 47?

In Chapter 47, a powerful analogy is used to illustrate the purifying power of saints. The text describes how the River Bhagirathi (Ganges), in the process of washing the feet of the world, becomes soiled with accumulated impurities and sins. To cleanse herself of this burden, the river yearns for the touch of a saint's feet, wondering, "When will the feet of saints touch me?" As Chapter 47 explains, the Ganges knows that without the dust from the feet of saints, there is no deliverance from her own accumulated sins. This metaphor highlights that the spiritual purity of saints like Sai Baba is so immense that even sacred entities like the Ganges seek it for their own purification.