Yevgeny Petrovich makes his point by telling his son Seryozha a story about an emperor whose son died of consumption (tuberculosis) from smoking. He has been trying to impress upon his son, in ordinary practical terms, the wrongness of smoking, but he doesn't get very far with him until he decides to create an imaginative little narrative about the misfortune that comes to this fictitious emperor upon the death of the emperor's son.
Several things stand out to me about this story. First, we're told that Yevgeny Petrovich, as a lawyer, is like all people involved in "practical life" in that he's unable to remember a single poem or fairytale by heart and therefore has to invent one for Seryozha. It's ironic, though, that he has this power of literary invention, as a writer or poet would have, to the degree of conjuring up on the spot a tale in which the little elaborations, like the description of the glass bells in the emperor's garden, fascinate Seryozha and impress the overall message upon him.
Second, "Home" is a kind of metafictional story in itself. It's self-referential in presenting us with a paradigm, in Yevgeny Petrovich's little story, of its own technique and that of fiction in general: the point is made in an imaginative, elaborated way instead of in a direct way. Last, the perception of smoking as dangerous, which Yevgeny Petrovich believes (correctly for his era and well into the twentieth-century) they still have no objective basis for, turns out to be ahead of its time, though in his telling, smoking causes consumption, the universally feared disease of the nineteenth century (as cancer is of our time). There is thus an additional irony in this subjective but ultimately accurate point embedded within the narrative.