Proverbs 27:16-18

New Catholic Bible

¹⁶ one might as well try to restrain the wind as to control her,
    or to pick up oil with one’s fingers.
¹⁷ As iron sharpens iron,
    so a man sharpens the wits of his neighbor.
¹⁸ Whoever tends a fig tree eats its fruit,
    and whoever looks after his master will be honored.