"Sonnet 138" is representing the devious side of man. While the speaker is getting older and out of his "prime," he believes that his "girl" is cheating on him. Even if that is the case, the writer confesses a deception of his own. He, even is the "girl" isn't, is cheating on her with another woman. The writer claims that the woman is trying to control him. This sonnet is mainly about betrayal, dishonesty, and lust.
             Written in a three-quatrain couplet structure, he states something about lies in all of them." Know she lies/false speaking tongue/simple truth suppressed/wherefore says she not." In all three quatrains, he also speaks of his wisdom and or age for that matter. The speaker is saying that even though I am old and stupid, I am not that much of an idiot. I know what is going on even if she doesn't tell me. An example of how the writer states his wisdom and age is," my untutored youth/my days are past the best/that I am old." This sonnet is made up off deception and lust.
             The writer uses the word "lies" in a way that is most unique. He uses it to portray her actual intentions for lust. She says that she would never keep any secret from him, but the writer thinks that she is as sly as a fox. By saying that his days are past the "best", the writer is saying that he is out of the prime of his life. No longer as "young" as he used to be. Meaning that he is wise to her actions, but decides to not let her know, off unfaithfulness.
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