Theme:     Sweetness turns Sour
Content:   2 quatrains of flattery of his subject's power then the 3rd. quatrain introducing doubt of his subject's worth by way of floral metaphor. Ending with a very powerful final couplet that resolves both themes. High contrast between the perceived qualities of the author and subject.

• "Those who possess oppressive authority but don't exercise it."
• This suggests a personal quality in the subject of not abusing their authority.

• "Those who can cause action in others whilst doing and showing nothing themselves."
• This introduces the concept of the subject's appearance being different from his influence and deeds.
• temptation slow is biblically echoed in "lead us not into temptation" of the Lord's prayer.
• This is an s sonnet heavily employing literal and phonetic use of the letter s.

• "These are the gracious who are sparing in the use of their assets."
• Possible pun on Mother Nature in husband nature's.
• Further heavy literal and phonetic use of s.

• "They are in full control of themselves whilst others are mere attendants of their skill."
• Further heavy literal and phonetic use of s.

• "People appeal to those of the same environment, but are mortal."
• This quatrain is where the flattering of his flawless and powerful subject turns to introducing their fallibility via floral metaphor.
• The subject's power in Q1 has turned into a flower here in Q3: a perishable, mortal, short-lived object.
• Further heavy literal and phonetic use of s.

• "If a thing of beauty becomes infected, then an uninfected baser item would be of greater worth."
• Comparing his subject as a flower with himself as a perceived weed.
• Dignity is very important here, I think. The author's dignity in his handling of his relationship with his subject distinguishes him from any perceived shortcomings such as his baseness.
• This flower / weed analogy is a favourite of the author's, most notably arising elsewhere in 69 & 124.
• Rhyming of dignity with die suggests the subject's dignity is dying.

• "Beauty is only skin deep; people are judged more by their deeds."
• Brilliant, famous last couplet.
• The subject, previously transformed from power to flower, now morphs for the final time to sour.
• The Lilies imagery may be derived from "I am the rose of Sharon, and the lily of the valleys" of Solomon 2:1, "His cheeks are as a bed of spices, as sweet flowers: his lips like lilies, dropping sweet smelling myrrh" of Solomon 5:13, "Consider the lilies how they grow: they toil not, they spin not; and yet I say unto you, that Solomon in all his glory was not arrayed like one of these" of Luke 12:27, and elsewhere.
• Extensive use of literal s in the closing couplet concludes the soft tone of the sonnet that contrasts with the sour message it contains.

The superficially flattering tone of the first 2 quatrains, I think, is supported by lines 1-2 which compliments those that don't abuse their power. Yet it turns on "That do not do the thing they most do show" that alludes again to the sonnet's "Don't judge a book by its cover" theme in an avalanche of "do's" that contradict the subject's actual inertia.Divine flattery follows in the next quatrain which is book-ended
by "rightly do inherit heaven's graces" and "their excellence". The sonnet points to the subject being someone like James I here, methinks: uncharismatic and claiming the Divine Right of Kings.

The author deliberately flatters to deceive in Q1-Q2, just as the "flower with base infection" in Q3 does.

The language is explicitly impersonal with no use of second person, but the subject matter and tone markedly change in Q3 with subjective, external observations of the subject's traits being replaced by infection existing at the subject's core. Q3 sets up the mighty final couplet like the bridge between a song's verse and chorus.

Especially notable is the extreme drop the subject suffers in the author's estimation: from being the absolute "sweetest" to the absolute "sourest" in line 1.

There is no explicit identification of "you", perhaps for fear of explicitly aggravating the intended subject: the author can say what he feels by making what are ostensibly general remarks without getting personal - it's rather like a remark one might make in the company of others intended for a specific person in the group but said in a way that it appears to be a general observation. I detect changes in tone from the person who is described as inheriting "heaven's graces" to the same subject who is now a "flower with base infection" to the no-holds-barred festering lily that smells "far worse than weeds". There's a progressive deterioration in the subject's condition that goes from unnoticeable, to inherent, to odious. I feel the backbone of the sonnet is the morphing of "power" (Q1-2) to "flower" (Q3) to "sour" (C).

It has the quality of being taken both personal and impersonal. The subject strikes me as someone with considerable power and authority that perhaps caused that ambiguity - probably not James I although he does seem to fit the subject of this sonnet very well to me.