Proverbios 27

Even if a foolish man is crushed with a hammer in a vessel among crushed grain, still his foolish ways will not go from him.

Aunque majes al necio en un mortero entre granos de trigo á pisón majados, no se quitará de él su necedad.

Though thou shouldest bray a fool in a mortar among wheat with a pestle, yet will not his foolishness depart from him.

Though you grind a fool in a mortar with a pestle along with grain, yet his foolishness will not be removed from him.