The Mishnah in tractate Sotah teaches that four kinds of people tear down the world from within: foolish pietists, crafty villains, sanctimonious women, and self-afflicting Pharisees. The Talmud then unpacks each one.
A chasid shoteh, a foolish saint, is the man who sees a woman drowning in the river and refuses to wade in because it would look improper for him to touch her. He congratulates himself on his modesty as she sinks. He has mistaken appearance for holiness, and a person dies for it.
A crafty villain? Rabbi Yochanan defines him as the litigant who reaches the judge before his opponent arrives and casually biases the court, weaving his story into the judge’s ear before any rebuttal is possible.
Rabbi Abahu adds another: the man who gives a poor person a single denarius so that his total holdings reach exactly two hundred zuz. The Torah exempts anyone with two hundred zuz from receiving gleanings, the forgotten sheaf, and the corner of the field (Leviticus 23:22). By pushing the poor man over the line, the crafty villain technically helps him — and strips him of every other right. Had the man stayed one zuz short, a thousand people could have continued to support him.
Each of these figures looks righteous from a distance. Up close, each one is quietly dismantling the world.