The speaker of this poem describes a beautiful woman, saying that she is both “dark and bright” in her beauty, like a cloudless, starry, black night sky. Just as this sky manages to be both dark and bright at the same time, so does this woman’s physical and spiritual beauty. She has “raven tress[es]”—or dark hair—and a sweet, serene face, made bright by her purity and “innocen[ce].” The speaker suggests that she is physically beautiful, like the night, rather than the day, because the night’s beauty is more mellow and “tender,” while the day is “gaudy” and rather garish. She is spiritually beautiful and “bright” as the stars in her virtuousness.

The speaker also claims that, were this woman even one bit darker or one bit brighter, her beauty would be marred and her grace “impaired” by the seemingly slight alteration. In other words, she is perfect, just as she is, and the combination of “shade” and “ray[s]” of light is perfect too. Any change, however small, would lessen her beauty. Her “shade” refers to the darkness of her beauty, her dark hair and perhaps her dark eyes. Her “ray” of light can refer to her spirit, which is “at peace” and tranquil because she is innocent and good.