8 The pious heart has its banquets, the proud heart has its banquets: for it was on account of the food of the proud heart, that he said, “with an insatiable heart.” How is the proud heart fed? If a man is proud, he is envious: otherwise it cannot be. Pride is the mother of enviousness: it cannot but generate it, and ever coexist with it. Every proud man is, therefore, envious: if envious, he feeds on the misfortunes of others. Whence the Apostle says, “But if you bite and devour one another, take heed that you be not consumed of one another.” You see them, then, eating: eat not with these: fly such banquets: for they cannot satisfy themselves with rejoicing in others' evils, because their hearts are insatiable.
Beware you are not caught in their feasts by the devil's noose....Just as birds feed at the trap, or fishes at the hook, they were taken, when they fed. The ungodly therefore have their own feasts, the godly also have theirs. Hear the feasts of the godly: “Blessed are they who hunger and thirst after righteousness: for they shall be filled.” If therefore the godly eats the meat of righteousness, and the ungodly of pride; it is no wonder if he is insatiable in heart. He eats the meat of iniquity: do not eat the meat of iniquity, and the proud in eye, and the insatiable in heart, eats not with you.
Source: The Enarrations, or Expositions, on the Psalms (New Advent)