30 But will he not be terrified by the punishments in Hades, of which we have heard, assuming also, as they do, many forms of torture? And who will be so senseless and ignorant of consequences, as to believe that to imperishable spirits either the darkness of Tartarus, or rivers of fire, or marshes with miry abysses, or wheels sent whirling through the air, can in any wise do harm? For that which is beyond reach, and not subject to the laws of destruction, though it be surrounded by all the flames of the raging streams, be rolled in the mire, overwhelmed by the fall of overhanging rocks and by the overthrow of huge mountains, must remain safe and untouched without suffering any deadly harm.
Moreover, that conviction not only leads on to wickedness, from the very freedom to sin which it suggests, but even takes away the ground of philosophy itself, and asserts that it is vain to undertake its study, because of the difficulty of the work, which leads to no result. For if it is true that souls know no end, and are ever advancing with all generations, what danger is there in giving themselves up to the pleasures of sense— despising and neglecting the virtues by regard to which life is more stinted in its pleasures, and becomes less attractive— and in letting loose their boundless lust to range eagerly and unchecked through all kinds of debauchery? Is it the danger of being worn out by such pleasures, and corrupted by vicious effeminacy? And how can that be corrupted which is immortal, which always exists, and is subject to no suffering? Is it the danger of being polluted by foul and base deeds? And how can that be defiled which has no corporeal substance; or where can corruption seat itself, where there is no place on which the mark of this very corruption should fasten?
But again, if souls draw near to the gates of death, as is laid down in the doctrine of Epicurus, in this case, too, there is no sufficient reason why philosophy should be sought out, even if it is true that by it souls are cleansed and made pure from all uncleanness. For if they all die, and even in the body the feeling characteristic of life perishes, and is lost; it is not only a very great mistake, but shows stupid blindness, to curb innate desires, to restrict your mode of life within narrow limits, not yield to your inclinations, and do what our passions have demanded and urged, since no rewards await you for so great toil when the day of death comes, and you shall be freed from the bonds of the body.
Source: Against the Heathen (New Advent)