Timothy slaps Phillip across the face in chapter 9 of The Cay. This is a super pivotal event and chapter for their relationship. By this point in the story, it is clear to readers that Phillip is a racist, ignorant bigot. He simply thinks that he is better than Timothy based on age and skin color. It's actually incredible that Timothy is as patient with Phillip as he is. This chapter begins with Timothy telling Phillip that they need some sleeping mats, and Timothy believes that Phillip is quite capable of weaving the mats despite being blind. In typical Phillip fashion, he gets frustrated and angry very quickly; however, this time he starts throwing racial insults at Timothy. Timothy isn't willing to put up with that, and he slaps Phillip in the face.
I tried again, but it didn't work. I stod up, threw the palm fibers at him, and screamed, "You ugly black man! I won't do it! You're stupid, you can't even spell."
Timothy's heavy hand struck my face sharply.
Phillip is shocked that Timothy would do such a thing, but the slap serves as a wake up call for Phillip. He realizes that he needs Timothy for physical survival reasons as well as emotional reasons.
Something happened to me that day on the cay. I'm not quite sure what it was even now, but I had begun to change.
As the chapter closes, readers get to see Phillip asking Timothy to be his friend and call him "Phillip."