They are illustrations of this true proverb: “A dog returns to its own vomit,” and “A sow, after washing herself, wallows in the mire.”
Like a dog that returns to its vomit, so a fool repeats his folly.
“If the infection returns and breaks out in the house after he has pulled out the stones, scraped the house, and it is replastered,
Jesus told them this parable, but they did not understand what he was saying to them.