Throughout the sonnet, the speaker emphasizes the importance of being true to oneself and not being fooled by outward appearances. He warns the reader that those who are beautiful on the outside but evil on the inside are like "painted sepulchers," which look beautiful from the outside but are full of dead bones on the inside. He also compares these people to "false perfumers," who sell perfume that smells good but is actually harmful.
The speaker ends the sonnet by saying that he would rather be "unregarded" than be like these people. He would rather be nobody, he says, than be someone who is not what he seems.
Here are some key lines from the sonnet that illustrate these themes:
* "For what care I who calls me well or fair,/That knows my frailties, and can judge my worth?/I do forgive him, though he be not fair,/For in my sight his beauty is unmatched."
* "But yet be blamed for this--that I am slow/To bless those fair eyes of yours with tears,/And slow to turn my thoughts to others' woes."
* "But be content to die, since she must live;/Your name is fair, though she take all the rest;/This, in the name of God, I beg of thee,/Let her not love thee lest she love too much."
Sonnet 147 is a powerful exploration of the contrast between outward appearances and inner reality. The speaker's message is that it is important to be true to oneself and not be fooled by outward appearances. It is better to be nobody, he says, than to be someone who is not what he seems.