This is a typical Shakespearean sonnet composed of 14 lines. This means that it has three quatrains (three four-line stanzas) and a final rhyming couplet, i.e., a two-line stanza.
The sonnet unfolds like a passionate argument. The first three stanzas build a case for "true love" being unwavering, like an "ever-fixed mark" amidst life's storms. Each quatrain uses vivid imagery—a ship navigating by a distant star or lips and cheeks escaping time's grasp—to illustrate love's resilience. Then comes the volta, which is also known as the thematic shift of the sonnet. Line 13, "If this be error..." introduces a dramatic change. The speaker confronts the possibility of being wrong, but their conviction remains unshakeable. The final couplet acts as a powerful declaration: "I never writ, nor no man ever lov'd." When faced with doubt, the speaker doubles down on their belief in true love's enduring nature.
The poem is composed in iambic pentameter, the most common meter used in Shakespearean sonnets. This meter consists of five iambic feet per line, where each foot contains an unstressed syllable followed by a stressed syllable. The consistent use of iambic pentameter throughout the sonnet provides a rhythmic regularity that echoes the poem's theme of unwavering love. This familiar meter not only lends the sonnet a musical quality, but it also reinforces the stability and predictability that Shakespeare attributes to true love.
The poem employs the traditional Shakespearean sonnet rhyme scheme, which is ABABCDCDEFEFGG. This pattern consists of three quatrains, each with its own alternating rhyme, followed by a final rhymed couplet. The rhyme scheme contributes to the organization of the poem's argument, with each quatrain developing a separate but related aspect of the central theme, culminating in the couplet that provides a conclusion to the sonnet's exploration of love.
In other words, Sonnet 116 balances exploration and then settles on a conclusion. The three quatrains meticulously dissect the concept of unwavering love, using metaphors and contrasting ideas. The final couplet delivers a resounding verdict, leaving the reader with a lasting impression of romance. This structure mirrors the poem's thematic journey, from exploration to resolute conviction.