Suppose that a human person commits one actual mortal sin, from which he never repents, and, subsequently, one hundred thousand venial sins. Now a person who is in a state of grace can have venial sins forgiven by any devout prayer, act of self-denial, or work of mercy, in cooperation with grace. But a person in a state of unrepented actual mortal sin cannot be forgiven of any sins, venial or mortal, until and unless he is reconciled to God. So that person goes to Hell deserving eternal punishment for the one unrepented actual mortal sin, and also deserving temporal punishment for the large number of unrepented venial sins.
God is Just, and so He cannot contradict His own Justice by failing to punish those one hundred thousand venial sins. But He also cannot justly punish those sins forever. Only unrepented actual mortal sin deserves eternal punishment. All actual venial sins, even those from which one is unrepentant, deserve only temporal punishment, a punishment that lasts only a limited period of time.
Suppose, in a different case, that a human person commits dozens of actual mortal sins, and he repents from every mortal sin with perfect contrition, or with imperfect contrition and Confession. Then, he commits one additional actual mortal sin and does not repent through the last moment of life. But he never did sufficient penance for any of his repented mortal sins.
God cannot contradict the Justice inherent in His own Divine Nature by failing to give the temporal punishment due for those repented and forgiven mortal sins. But He also cannot justly punish those repented sins forever. Only unrepented actual mortal sin deserves eternal punishment. All repented and forgiven actual mortal sins deserve only temporal punishment.
Therefore, I propose that the sufferings of Hell at first include punishments for unrepented venial sins, and for repented and forgiven mortal sins (if there is unremitted temporal punishment due) as well as for the unrepented actual mortal sins that were the cause of the individual’s damnation. Then, once the individual in Hell has suffered sufficiently for those venial sins and repented mortal sins, that punishment ceases, and only the punishments for unrepented actual mortal sin continue forever.
There is no other tenable conclusion. The justice of God cannot fail to punished damned souls for venial sins or repented mortal sins, just as the souls in Purgatory are punished for those sins. For if God failed to punish the guilty in Hell to the full measure that they deserve, then He would be contradicting His own teaching through the Prophet Daniel. For Daniel condemned two leaders of Israel for “judging unjust judgments, oppressing the innocent, and setting free the guilty” (Dan 13:53). God cannot give the damned in Hell any more or less punishment than they deserve.
Neither can God punish the souls in Hell forever for any sins other than unrepented actual mortal sin. For His Church teaches that only unrepented actual mortal sin deserves unending punishment in Hell. Therefore, some of the punishments of Hell are eternal, but other punishments are temporal. Those temporal punishments in Hell decrease over time, as each venial sin or repented mortal sin is expiated in its temporal punishment. Finally, when the soul has suffered sufficiently for all its venial sins and repented mortal sins (those which were not forgiven in guilt or punishment in this life), thereafter the soul suffers in Hell only for its unrepented actual mortal sins.
The interesting conclusion of this analysis, then, is that the sufferings of Hell, for many of the souls there, decrease after a while. But upon decreasing a certain limited amount, the remaining punishments (those for unrepented actual mortal sin) continue forever.
The above text is an excerpt from my booklet: Heaven, Hell, Purgatory, and Limbo
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