The final line’s meter contains several aberrations from the normal iambic pentameter. Rather than following the typical alternating rhythms of unstressed and stressed syllables, the line has two unexpected stresses: “Lil-ies that fes-ter smell far worse than weeds.” The initial stress in “Lilies” mirrors the same stress in poem’s first word, “they.” Both “lilies” and “they” refer to the same subject: people who wield the power of beauty. Both words exhibit this power in their conspicuously dominant metrical upheavals.

The phrase “by their deeds” connects the souring of the lilies to the theme of righteous actions. A central topic in Christian theology is the question of whether it is personal faith or good works that place one in alignment with God. In this line, the speaker takes the position that it is one’s works, or “deeds,” that determine one’s value. It is those given the most from heaven who have the greatest responsibility to behave morally.

This final line underscores the theme of the poem: the corruption of the best of things makes the worst of things. This idea comes from a proverb “optima corrupta pessima” —the best things corrupted become the worst. In other words, when something is in its perfect form and falls for one reason or another, it is more tragic, more corrupt, than any other kind of fall.

The weed could also be interpreted as the speaker who self-consciously recognizes that his dalliance with the youth corrupts both his beauty and class status. However, within this metaphor, in which the weed “outbraves his dignity,” the speaker suggest that there is an action that can elevate the “base weed.” This could be interpreted as the speaker’s poetry being able to give him dignity.

In repeating “base,” the speaker suggests that the “base infection” is the “base weed.” This comparison underscores the extended class metaphor that exists throughout the poem. The “base weed” could be interpreted as a member of the lower class tainting the high class “flower” with its lower social rank.

With this Biblical allusion, the speaker brings up the tension between one’s external appearance and internal qualities. While the flower is essential to summer and makes summer sweet, because it only lives for itself, it is actually internally corrupt. It is sweet to the physical systems on earth but rotten in the eyes of God.

These two lines are an allusion to the Bible, “For none of us liveth to himself, neither do any die to himself. For whether we live, we live unto the Lord: or whether we die we die unto the Lord.” (Romans 14:7-8). This passage from the Bible claims that all men, regardless of status, external appearance, or good deeds, live and die with God; essentially, they should not be judged by fellow men because God judges all mankind.

This line claims that beautiful people, gifted by “heaven’s graces,” may live morally bankrupt lives. Even if they try to act in faith through a personal relationship to God—being sweet “to the summer”—, they may remain closed to the world. It is this closed-off quality, discussed in line 10, that prevents them from performing the righteous actions essential to a well-lived life.

“Flower" repeats the rhyme of the first line “power” and creates a parallel between the stoic beautiful people discussed in the first two quatrains and the “flower” discussed at the end of the poem.

The “summer” serves as a representation of God, the flower’s creator, suggested by the possessive nature of their relationship. This quatrain introduces the theme of whether one’s faith in God is best expressed through good deeds or through personal faith.

The metaphor of aristocratic land ownership continues. The alternative to owning, and thus controlling, one’s beauty is to be “steward” of it. A steward tends the land of another, rather than owning it. A beautiful person who acts as “steward of their excellence” allows their beauty to be used according to the agenda of others.

Further developing the aristocratic metaphor, the speaker discusses the different ways in which beautiful people can cultivate their gift. He proposes two options, presenting them through metaphors of land ownership. In medieval and Renaissance Europe, the vast majority of wealth belonged to landowners. As the speaker phrases it, those who practice self-control are like “lords and owners of their faces,” not allowing their beauty to be used by others.

“Expense” has connotations of reckless spending and waste. It also has sexual undertones. The connotations of this word point to the extended class metaphor threaded throughout the poem. Those who have inherited “heaven’s graces,” beauty and high social class, must keep both beauty and class pure by preventing “expense”— in terms of reckless actions, wasteful spending, or sexual affairs with those of lower status.

“Husband” means the care, breeding, and cultivation of plants and animals. This meaning of the word reflects the idea of “inherit” from the previous line, as landed gentry “inherited” land which they would then have to cultivate. Because this word takes place in a love poem, it evokes the marital definition of “husband” as well.

“Heaven’s graces” refers to both one’s beauty and class here. This metaphor suggests that these two elements of social power come from God, which in turn elevates both beauty standards and the social hierarchy.

The sonnet’s second quatrain develops an extended aristocratic metaphor. Beautiful people are akin to landed gentry who “inherit” the wealth of their appearance. Thus, the beauty itself is like the land, which can be tended in different ways.

“Temptation” has religious connotations from the Lord’s Prayer —”and lead us not into temptation.” This suggests that the “stone, unmoved, cold” demeanour characterized by the first three lines is positive despite the speaker’s admonishing tone. The stoic state allows these beautiful people to resist temptation. This positive message is delayed until the end of the quatrain suggesting tension between the message of the poem —those with beauty and power should exercise restraint —and the speaker’s opinion of this restraint.

The words “unmoved” and “cold” carry a nuanced meaning. While these words take on a negative connotation, the speaker actually uses them to depict an ideal model of behaviour. To the speaker, “they that have power” ought to practice restraint and self-control. In his view, beautiful people should not use their beauty to take advantage of others. Rather, they should be “unmoved, cold” in the face of temptation.

“Stone” takes on two connotations. On one level, to be “as stone” suggests an impersonal demeanor—a “cold personality,” as the fourth line suggests. “Stone” may also refer to a “lodestone,” a naturally-occurring magnetic mineral. This connotation accounts for the magnetic beauty of “they that have power.”

The repetitive use of “do” in the first two lines is intentionally contradictory. The word brings up connotations of action, and yet the underlying point of the lines is to encourage inaction. Thus, the repetition of “do” mimics the “temptation” in line 4.

The word “they” noticeably alters the iambic pentameter of the rest of the poem. As the line’s first syllable, it ought to be unstressed. Instead, it takes a stress, inverting the first foot from an iamb to a trochee. In a sense, “they” subjugates “that” in a manner that imitates the “power to hurt.”

The content and phrasing of the first line comes from the Latin proverb “Posse et nolle, nobile,” meaning “To be able to harm, and not to do it, is noble.” As the poem progresses, it becomes clear that the type of power the speaker alludes to is beauty, narrowing the subject to the fair youth.

The use of “they” in the opening line introduces the poem’s central idea as a broad word of caution. Though the youth falls into the camp of “they that have power,” the speaker is careful not to launch into an accusatory tone.