8 But will it be thus always, that the ungodly have power over the righteous? It will not be so. The rod of the ungodly is felt for a season upon the lot of the righteous; but it is not left there, it will not be there for ever. A time will come, when Christ, appearing in his glory, shall gather all nations before Him. And you will see there many slaves among the sheep, and many masters among the goats; and again many masters among the sheep, many slaves among the goats. For all slaves are not good— do not infer this from the consolation we have given to servants— nor are all masters evil, because we have thus repressed the pride of masters. There are good masters who believe, and there are evil: there are good servants who believe, and there are evil. But as long as good servants serve evil masters, let them endure for a season. “For God will not leave the rod of the ungodly upon the lot of the righteous.” Why will He not? “Lest the righteous put forth their hand unto wickedness:” that the righteous may endure for a season the domination of the ungodly, and may understand that this is not for ever, but may prepare themselves to possess their everlasting heritage....
Source: The Enarrations, or Expositions, on the Psalms (New Advent)