The storytelling in Ceremony refers not only to the folklore of Native American myth, but also of the cyclical nature of human development and reliance on nature.
Since Native American culture is distinctly oral, including their history, moralities, and even medicine. It's so important to them that elders in their community are often regarded as official storytellers, their tales of which are treated as communal events.
They use rhythm, song, and repetition ala poetry to get their multitude of listeners to remember the lessons, which is present in Silko's Ceremony as well. This tells us as readers that we should remember these lessons too, and that we are not excluded. Tayo learns this over the course of the novel as he journeys to heal himself as an outsider, as he remembers and reenacts the old stories. Afterwards, he reconnects with his community by accepting the things that happened in the war and the trauma before that, settling by being content with the old stories that remind him that others before him have all had similar - if not the same - experiences. It showed him that he wasn't alone, and that there is no such thing as a condemning force that can stagnate one until death. One can always look back and adapt.
Link to blog post about "Green Corn & Sacred Fire."