Chapter 8 documents several of Cathy's sins as a young child, including the murder and immolation of her parents. Cathy herself disappears after the murder, leaving the police to scramble for a scapegoat to charge with her crimes. The police do indeed choose a man—one with some kind of intellectual disability, such that he confesses to anything the police ask him about. After the trial, the judge scolds the police for this, using both hyperbole and Biblical allusion to explain why the officer's actions were wrong:
"He would have admitted climbing the golden stairs and cutting Saint Peter's throat with a bowling ball," the judge said. "Be more careful, Mike. The law was designed to save, not to destroy."
In the above passage, the judge uses hyperbole to exaggerate what the "feeble-minded" man would theoretically admit to, devising an outrageously unrealistic scenario to emphasize this man's vulnerability to manipulation. In this scenario, the judge alludes to Christian traditions, referencing the "golden stairs" of heaven and "Saint Peter," who is traditionally believed to guard heaven's gates. While it is outrageous to imagine the "feeble-minded" man on trial climbing the staircase to heaven and murdering Saint Peter, it is even more outrageous to picture him cutting the saint's throat with a dull bowling ball.
In Chapter 8, Steinbeck meditates on sexuality at length, describing the phenomenon of a young child first discovering her own relationship to sex and desire. As Cathy learns about sexuality, she also learns how to manipulate it in service of her own personal gain. Steinbeck uses hyperbole in this passage to evoke the gradual process of learning about sexuality's social stigma:
Cathy learned when she was very young that sexuality with all its attendant yearnings and pains, jealousies and taboos, is the most disturbing impulse humans have.
The hyperbole in this passage emphasizes the outsized effect sexuality has on perceptions of individual morality. Sexuality is far from the most disturbing impulse people have: the desire to murder, torture, or abuse would rank much higher. While sexuality has the capacity to be violent and harmful, it is not inherently so, unlike many other human impulses one could name. Given commonly held cultural views on sexual expression, however, a young child like Cathy might wrongfully assume that having sex is worse than committing an actual crime.
More than simply "disturbing" people on an emotional and spiritual level, sexuality has the ability to "disturb" the social order—family structure, inheritance, religion. Unconventional expressions of sexuality represent legitimate threats to systems of economic, political, and religious power and consequently must be curtailed. Children like Cathy must adapt their natural impulses to avoid "disturbing" the system.