Night and Day (Symbol)
In the first stanza, the speaker separately compares the two main characters to "the golden splendor of the day" and "the sable pride of night." This highlights the contrast of their skin colors, but does so in a way that portrays them as being equally radiant. The images work together to communicate the same point in different contexts. The symbolism of night and day here functions to represent the two main characters' equality, and beauty, within their loving relationship.
Lightning (Symbol)
In the third stanza of the poem, the speaker compares the couple to lightning, stating that they "see no wonder" in the fact that lightning "should blaze the path of thunder." What the speaker means is that the couple cuts through the noise of other people's judgmental comments and stares in the same way that lightning "blazes" the way that thunder merely travels. They seem to suggest that thunder is just the aftershock of lightning, in the same way that these criticisms are forgettable remnants. Lightning symbolizes both the brightness of their meaningful relationship and the way in which they cut through the surrounding chatter and disapproval.