Sonnet 55 by William Shakespeare is a testimony to memories of a loved one. Shakespeare is saying, as mentioned in Post #3, that the memory of the departed loved one will live on because of the words of the sonnet - that nothing will prevent these words from having a life of their own; these words that celebrate a life will outlive monuments of stone.
Shakespeare says that the dearly departed will live on more brightly because of the contents of this particular sonnet. The sonnet is a testament to this person's life. War no anything else will
The living record of your memory.
The person who has died will continue to live in this poem, and in the hearts, minds, and eyes, of loved ones left behind, until the day of this person's judgement at the resurrection.