Despite consisting of three stanzas, “She Walks in Beauty” is in fact structured in two halves, each of which is dominated by a distinct opposition. The first ten lines of the poem concern the opposition of light and dark, and how, through their harmonious balance, this opposition yields beauty. In the first six lines, the speaker develops a comparison between the woman’s beauty and that of a cloudless night sky. Just as the twinkling of starlight subtly illuminates the otherwise dark sky, so too does the gleam in the woman’s eye slightly brighten her overall appearance. The speaker continues the develop this thought about the harmony of light and dark after the transition from the first stanza to the second (lines 1–7):

     One shade the more, one ray the less,
     Had half impaired the nameless grace
     Which waves in every raven tress,
     Or softly lightens o’er her face.

Here, the speaker asserts that even a little change in the dark/light balance would threaten the woman’s delicate beauty, which he now sees in the contrast between her dark hair and light skin.

However, directly following the lines quoted above, the speaker shifts to a consideration of another opposition. In this case, the opposition concerns the relationship between the woman’s physical beauty and her virtuous character (lines 11–12):

     Where thoughts serenely sweet express,
     How pure, how dear their dwelling-place.

In these difficult lines, the speaker makes a speculative leap. He describes how the beauty of the place where the woman expresses her thoughts (i.e., her face) indicates the purity of the place where the thoughts themselves dwell (i.e., her mind). In other words, after observing the beauty of the woman’s physical exterior, the speaker makes an inference about the virtue of her character. The speaker goes on to develop this thought more fully in poem’s third and final stanza. There, he explains how “the smiles that win” (line 15) on the woman’s cheeks and “the tints that glow” (line 15) on her brow can be interpreted as signs of virtue. He claims that these signs “tell of days in goodness spent” (line 16) and make manifest “a heart whose love is innocent” (line 18).