Truth and reporting
This motif describes the function that Goethe plays in his own life, to report his point of view as truthfully as he can. He doesn't do this by literally transcribing every passing moment, but rather, through art, he tries to communicate something about each moment or each day that shows the day in its essence in a more acute way than strict reporting would allow. And yet, he does sometimes report literal detail. The result is a tone that is both obvious and mysterious.
The archetypal journey
This vacation takes Goethe away from his role and his community into the wilderness, through other communities, in a long circuit that comes all the way back home. The journey takes him home. This forms an archetypal motif of the hero's journey. This is more obvious because Goethe is a leading authority on writing and stories, so he considers these concepts openly in the writing, juxtaposing his sense of self to the way one might view a book.
The fairy-tale symbol
He says about this writing that it is both truthful and "a graceful fairy-tale." This underscores his awareness of the archetypal quality of his own experience, but remember, Goethe is writing from the early 19th century, a long time before "fairy-tale" meant anything related to Disney films or something. He is not commenting on the sweetness of his trip, but on the sublime nature of it. Where he comes from, a "fairy-tale" is sublime and sometimes even horrifying, so that his comment is that the trip has a strange, transcendental quality.
Death as a consideration
Death occurs throughout his journeys as an object of his fascination. When the thought crosses his mind (as it often does) that the truth "journey" is his life, and the "going home" is a symbol for death, he cannot help but fixate on that. He talks about death by invoking literary motifs for that discussion. He quotes adages about death and discusses the literary discussion of death. Because much if not all of literature is about human life and human experience, it is also about death, because that is the end of every human narrative. For some reason, traveling makes him think about dying.
Italy as a symbol
Because of the history of Italy, the country serves as a tangible symbol for time and the passage of time. Goethe reflects on the years of his life, using the aging towns and cities of Italy as a metaphor for his own self. He explores the countryside of Italy noticing that there is a timelessness about nature that juxtaposes the fixity of human society, because the buildings age, but the fields and trees are timeless and seem nearly eternal.
