I feel that the last three lines is the theme of the poem greatest. These lines read, “So Eden sank to grief, So dawn goes down to day. Nothing gold can stay.” The third to last line talks of an example of something great falling because nothing good can stay forever. The next line is exactly like the example in the book, showing the sadness in lost beauty. The last line is what the whole poem is about, it is saying all is gold for a while, but not forever.