What is a summary of sonnet 147?

In Sonnet 147, the speaker compares his beloved to a summer day, praising her beauty and comparing it to the warmth and splendor of nature at its peak. However, the speaker also laments the fleeting nature of beauty and youth and acknowledges that, like summer, these qualities will eventually fade: "And every fair from fair sometimes declines."

Additionally, the speaker alludes to the cycle of nature in which new life and growth come after death, and he suggests that the beloved’s beauty and virtue will live on in the memory of those who have loved her: "But thy eternal summer shall not fade, nor lose possession of that fair thou ow’st; nor shall death brag thou wand’rest in his shade, when in eternal lines to time thou grow’st."

The sonnet ends with a couplet that affirms the power of the beloved's beauty and virtues to transcend time and to make her immortal in the poet’s verse.