The poem’s form is that of a conventional Elizabethan sonnet. Each of its fourteen lines contains ten syllables. The poem consists of three distinct quatrains; the first two are complete sentences, and the third is directly linked to the concluding couplet. It begins with a series of images highlighted by the cadence which is produced by Shakespeare’s steady use of anaphora in the first quatrain.
The extensive repetition of “some” (seven times in four lines) stresses the idea which will be refuted by the following two quatrains and couplet. This technique strongly links the lines of the initial quatrain. When this link is broken in the second and third quatrains, the isolation of the narrator is raised to a peak that climaxes in the final couplet.
The anaphora also seems to debase those who are primarily interested in things other than love. This attitude produces a certain irony in the poem’s shift to the singular in the second and third quatrains, where an image of superiority is produced. The narrator, who seems to be deriding those who care so much for items and ideas which cannot reciprocate their affection, actually appears pompous by placing himself above the others.
This technique also produces an oxymoron which is as startling as it is ironic. Love should not be a wretched affair, yet the psychological realism of this emotion is often just that. Love does cause pain and concern as well as a feeling of contentedness. The usual practice of the sonneteer was to glorify love; the heights of this devotion could reach nearly absurd proportions. Shakespeare chooses to vary from this technique, and the result is a shocking revelation which clearly illustrates the point.
Shakespeare’s use of surprise or negation in the closing couplet further elaborates the nakedness a lover feels when he expounds his feelings for his beloved. The effect elicited by this negative couplet is a stark contrast to the usual pouring out of love and devotion found in the sonnets of Petrarch and others. It is the very twist of this conclusion that ties the sonnet into an organic whole and makes the poem so effective. All the attributes mentioned in the initial quatrain parallel the emotions of the final quatrains and couplet.
As different as this conclusion may be, Sonnet 91 retains many of the elements which are traditionally included in the genre. The anaphora of the initial quatrain gives way to the expected love analogy. Certainly the narrator adores and idolizes his beloved. The explication of such emotions is the normal function of the sonnet form. It is the irony of the poem’s shift in the closing couplet that differentiates it from more traditional sonnets.