Not Time's fool

Time is pictured as a reaper, carrying a curved sickle that cuts down youth and beauty, as a farmer cuts down crops.

Rosy lips and cheeks fall within the sweep ('compass') of Time's sickle: looks fade as people grow old. But love is not Time's fool: it is not made a fool of by time. It does not change with the brief hours and weeks, but lasts to the end of the world.

The final couplet is a bold challenge: if I am wrong about this, then I never wrote anything, and no man ever loved. Since he obviously did write, and people obviously have loved, his claim must be true.

Love is seen as a lasting force, larger than any person.

A Shakespearean sonnet has fourteen lines: three quatrains (groups of four lines) and a final couplet (two lines). Its rhyme scheme is ABAB CDCD EFEF GG. The quatrains develop the idea; the couplet sums it up, or adds a twist.