The quote from John Updike's "The Witches of Eastwick" compares wickedness to food in a metaphorical way, suggesting that engaging in immoral or harmful actions can lead to a compulsion to continue. Just as indulging in food can create a desire for more, allowing wickedness into one's life can lead to a cycle of increasing misdeeds. This reflects on human nature's propensity to seek gratification, often without considering the consequences.

Updike's portrayal highlights how quickly one can become ensnared by their own vices. The imagery of the "expanded gut" symbolizes how engaging in wickedness can alter one's moral compass, making it easier to commit further transgressions. This suggests that once someone begins to indulge their darker impulses, it becomes increasingly difficult to break free from the cycle, emphasizing the allure and danger of succumbing to temptation.