In creative work, strive to marry form with function. The content of the work should align well with its message, theme, or argument. There should be symmetry between the way in which a story is told and its content.
Choose details that reinforce or accent the theme. In writing, this might extend to word choice. For instance, even the sound of a word has a quality that can create an impression or meaning apart from its literal definition; consider, also, the rhythm or cadence of a sentence, all of which should suggest the broader theme of the text. As Emerson said, "Write with your ear."