Who is Vyasa in the nonfiction book, Thou Art That?

Vyasa, who is called the Homer of India, is a saint, born of an unusual virgin nicknamed "Fishy-Smell" for the manner of her conception. She is impregnated on a ferry by a yogi, who restores her virginity. At his birth, Vyasa tells his mother he will reappear when she needs help and promptly leaves. In the end, he does come back to end her suffering.