How does the author describe the qualities of a powerful story and an ideal listener at the beginning of Chapter 21?

At the start of Chapter 21, the author reflects on the dynamic between a storyteller and the audience. He suggests that a speaker's words are rendered useless or 'gone in vain' if the listener does not emotionally react—specifically, if they do not 'sway upon hearing them' or if the 'hair on the body does not stand on end.' The chapter further argues that narrations are 'futile' if they fail to delight the listeners, cause their throats to choke up with emotion, or bring tears of love and joy to their eyes. This sets a high standard for spiritual storytelling, emphasizing that its true purpose is to evoke a deep, visceral, and emotional response in the audience, which is a testament to the captivating power of Baba's own speech and actions.