The structure of the sonnet is separated into three quatrains and ends with a couplet. The sonnet is a plea to the young man that he procreate and not withhold his beauty from the world to fight against the passage of time and to continue his legacy.
Speaking of the young man’s beauty, the sonnet suggests that unlike the changing and passing of seasons, Summer, Autumn, Winter, and Spring, the young man’s beauty will preserve through the passage of time. Though the young man will physically die, the poem itself, as long as it exists and is read, will encapsulate the young man’s beauty for all eternity.
The speaker sets out to explain how the passage of time affects human life. The first quatrain likens the passage of time to a tide approaching the shore, while the second quatrain is concerned with the passage of human life as metaphorized by the rising and eventual setting of the sun. Finally, the third quatrain personifies time as a creature that devours the youth and beauty of the beloved. In the final couplet, the speaker argues that art will preserve in the face of time’s destruction.
The speaker likens the bleakness of winter and the moment right before the end of twilight as metaphors to contemplate his anxieties regarding his old age, and eventual passing. While the first two quatrains employ cyclical metaphors, the seasons and the parts of the day, the third quatrain’s metaphor of the burning ash deal with the finitude of youth and the speaker’s acceptance of what can ever be again once the fire has burnt out. The couplet, directed to the beloved, urges him to acknowledge the impending death of the speaker and to love him increasingly while he is alive.
The subject of the first part of the sonnet speaks about a person whose beauty influences others, but they themselves do not actively participate in effecting the world around them, rather, their very existence, that which is cold, and reserved, impacts those, to an almost frustrating degree. In the second part, the metaphor of a beautiful flower that withers away and begins to smell is related to weeds, and in this regard, the speaker suggests that a flower that has rot is worse than a weed that was never beautiful to begin with. The speaker in this regard turns around and though in the first part suggests that the person does not reciprocate or actively participate in the effects that they have on people around them, their inaction, or lack of feeling, is indeed an act that sours and hurts the ones that might try to love them, effectively turn them away from being a beautiful subject.
Though the speaker reveals it is late Summer, the speaker’s sense of separation for his beloved is compared to the barrenness of winter. Rather than anticipating the bounty that comes with the fall harvest, the speaker feels empty. Even the birds’ songs, which are typically cheerful, only sound of melancholy and longing.
The speaker defines love as permanent and untarnished by the changes in a loved one, he then goes on to metaphorize love as a star that guides ships on the ocean and that can weather any storms. The speaker also defines love as unaffected by time, in this regard, time is immortal and timeless. The speaker concludes the sonnet by asserting that if any of the statements he has made about love are incorrect then it is impossible that no one has ever loved in their lives.
The speaker explores lust in three different stages, lust as anticipation, lust as it occurs in consummation, and lust in its aftermath, which translates into a sense of shame. Though lust, as the speaker suggests, always ends with this feeling of shame, no one is free from being compelled by its force, and thus no one is free from suffering the shame that follows. In that regard, the speaker implies that lust and shame are inextricably linked.
The speaker’s mistress’s eyes do shine like the sun, nor are her cheeks as red as roses, and even her voice is not as beautiful as songs, but the love the speaker has for his mistress is beyond compare, and thus it is love in its reality and not in metaphor that the speaker finds the beauty of his mistress.
The speaker questions why the soul gives up so much for the fleeting passions and finite existence of the body. In the third quatrain the speaker makes a plea to the soul to focus on its own improvement in favor of the body’s so it might grow and prosper. The final couplet suggests that only by doing so will the soul be able to attain eternal life.