Chapter 36 mentions a promise was given in the previous chapter. What was that promise?

The beginning of Chapter 36 urges the reader to "please pay attention to the promise that was given" in the preceding chapter. However, the provided text for Chapter 36 does not specify or reiterate what this promise was. The narrative immediately transitions into a philosophical discussion about the nature of Sai's stories, describing them as the "very water of self-bliss." Based on these excerpts alone, the content of the promise mentioned as a carryover from the previous chapter remains undefined.