What does the author of Sai Satcharitra consider to be the signs of a truly impactful spiritual story at the beginning of Chapter 21?

At the start of Chapter 21, the author, Hemadpant, lays out specific criteria for what makes a spiritual narration effective and worthwhile. He suggests that a speaker's words have gone in vain if the listener is not deeply moved. According to the text, a truly impactful narration is one in which "the listener does not sway upon hearing them, if the hair on the body does not stand on end." He further states that narrations are futile if listeners are not delighted, if their throats do not choke up with emotion, and if tears of love and joy do not flow from their eyes. This sets a high standard for the power of divine stories.