Shakespeare’s central theme is the opposition between the transitory, delicate nature of beauty and the devastating effect on beauty of mortality and its principal instrument, time. The opening questions seem rhetorical, indirectly arguing the poet’s conviction that beauty is no match for aging and death. The final two lines dispel the gloomy predictions implicit in the questions, however, by pointing to the power of the written word to sustain its subject—in this case, beauty. As the poem advances through the first two quatrains, the changes in the images of time suggest an increase in the implacable strength of time, which only “o’er-sways” in the second line but turns to a “rage” and then a “wreckful siege of battering days” attacking such impressive things as “rocks impregnable” and “gates of steel.”

The final two lines, by opposing “black ink” with the light which the poet’s love emits, leave the reader with the central conflict of the poet’s vision: light (beauty) is opposed by darkness (black ink), and therefore utter annihilation. The balancing imagery of the final line suggests a resolution to this conflict and so ends the poem on a bright note, literally on the word “bright” itself: The poet’s love, expressed in this written sonnet, is the one force that can successfully oppose time and death. The word “still” in the last line introduces a paradox. If “my love” is “still,” meaning lifeless, it cannot “shine,” yet it does, or might; if it is indeed motionless, it cannot “still” be shining, yet it may, in “black ink,” and in that form, it can forever oppose the destructive motion implicit in the phrase “this rage.” The poet’s skill is the only force that can reverse the effects of aging and stop time’s forward motion, which carries all things to their death. The poet’s hand becomes the “strong hand” (line 12) that can indeed hold time’s “swift foot back.” The surprise is that the strength is not physical but poetic.

A more subtle surprise is that, while appearing to address what male lovers are expected to address, a beautiful woman, Shakespeare here focuses on beauty, perhaps in keeping with the poem’s general air of indirection—rhetorical questions develop the poet’s subject all the way to the final couplet in place of direct argument. The poem seems to suggest that to be any more direct, by addressing his beloved directly, he would “expose” her to time’s onslaught. By remaining as “hidden” and insubstantial as “Time’s best jewel,” the object of his love may be saved. If the “black ink” of his poem draws a curtain of darkness before the face of his beloved, her beauty may nevertheless shine through the love that the poem expresses.

In keeping with the delicate indirection of the poem, the poet makes only slight references to the sexual aspect of his love, principally in the third quatrain, where “impregnable” subtly suggests where the poet’s mind is going—time is a ravager of beautiful women, one way or another. Hints of ravishment continue as the poet references “gates of steel” and concludes in his using “spoil” (plundering) that beauty cannot “forbid.”

The structure of the final line reflects brilliantly the poem’s resolution, the inky blackness of annihilating time at one end of the line and, at the other, the redemptive light of the poet’s love. Between these two states is the poet’s “love,” the fulcrum that forever separates and balances them.