In John Milton's "How Soon Hath Time," the tone of the speaker in the octave seems somewhat chagrined. The speaker regrets that he has lost his twenty-third year to the "thief" of Time. In addition, he bemoans that he is not yet "blossomed" and has a "semblance" that belies his age; that is, he wishes that he were more manly in appearance. His youthfulness is spoken of with a regretfulness.
However, in the sestet, the speaker's tone changes as he becomes resigned to the will of the heavens and places his trust in the "great Taskmaster." In this sestet, the speakers word choice differs from the octave, as well. For, more poetic words are used in the octave--e.g. the "Time, the subtle thief of youth,"--while words with religious overtones are employed in the sestet--"will of heaven," "the great Taskmaster."