Earlier in his life, Hightower thought that he had won for himself the privilege of remaining uninvolved in life. But gradually, since the appearance of Lena, he has slowly been drifting back into the stream of life. His re-entry into life is seen through the agency of Byron. Even though in Chapter 16 he rejected Mrs. Hines' pleas to help Joe Christmas, he does allow himself to go out to help Lena with the birth of her child.
The act of giving life to Lena's child becomes symbolic of Hightower's restoration to life. Immediately after this act, he walks back to town thinking that he will be unable to sleep. This is still an unconscious resentment of being drawn back into the stream of life, even though the aid that he gave to Lena was voluntary. Thus, when Hightower does sleep peacefully, we can view this as being symbolic of Hightower's regeneration as a human being. This is also seen in the fact that he notices for the first time the peaceful serenity of the August morning. He even realizes his own reawakening when he recognizes that life and involvement are still possible. He views the birth as a good sign and as an omen of goodwill. Therefore, this act of involvement and responsibility has restored Hightower to the human race. Another connection between Lena and Joe is presented when Joe's grandmother aids Lena during childbirth. Lena even becomes confused as to the paternity of the child and begins to think that Joe Christmas is the child's father.
Chapter 18 acts as a type of comic interlude with Byron arranging for Lena to meet Brown. In the midst of a novel dealing with Joe Christmas' tragic plight, this chapter reminds us of the basic incongruity of mankind. It shows Byron's dedication and love for Lena and prepares us for his final action of following Lena. Yet the action is detached and comic partly because of Lena's dogged determination to follow Brown when he leaves, and also because of Byron's absurd behavior. In juxtaposition to the comic are the tragic implications at the end of the chapter when Byron hears that Christmas has been killed.