Can you explain the metaphor of the Ganga river used at the beginning of the provided text?

In the excerpts from Chapter 47, the Ganga river is personified to illustrate the purifying power of saints. The text explains that the river feels burdened by the sins of the countless people who bathe in it and has "exiled herself" in a state of impurity. She longs for deliverance, asking, "When will the feet of saints touch me? When will they come to bathe within me?" As Chapter 47 clarifies, the river knows that contact with saints is the only way "to wash away her accumulated impurities." This metaphor serves to elevate the status of saints like Sai Baba, suggesting their presence is so purifying it can cleanse even the sacred Ganga of the sins it has absorbed.