2 Corinthians 7:10

'Therefore.' he says, 'though I did regret before I saw the fruit and the gain, how great they were I do not regret now.' For such a thing is godly sorrow. And then he philosophizeth about it, showing that sorrow is not in all cases a grievous thing, but when it is worldly. And what is worldly? If thou be in sorrow for money, for reputation, for him that is departed, all these are worldly. Wherefore also they work death. For he that is in sorrow for reputation's sake feeleth envy and is driven oftentimes to perish: such sorrow was that which Cain sorrowed, such Esau. By this worldly sorrow then he meaneth that which is to the harm of those that sorrow. For only in respect to sins is sorrow a profitable thing; as is evident in this way. He that sorroweth for loss of wealth repaireth not that damage; he that sorroweth for one deceased raiseth not the dead to life again; he that sorroweth for a sickness, not only is not made well but even aggravates the disease: he that sorroweth for sins, he alone attains some advantage from his sorrow, for he maketh his sins wane and disappear. For since the medicine has been prepared for this thing, in this case only is it potent and displays its profitableness; and in the other cases is even injurious. 'And yet Cain,' saith one, 'sorrowed because he was not accepted with God.' It was not for this, but because he saw his brother glorious in honor; for had he grieved for this, it behoved him to emulate and rejoice with him; but, as it was, grieving, he showed that his was a worldly sorrow. But not so did David, nor Peter, nor any of the righteous. Wherefore they were accepted, when grieving either over their own sins or those of others. And yet what is more oppressive than sorrow? Still when it is after a godly sort, it is better than the joy in the world. For this indeed ends in nothing; but that "worketh repentance unto salvation, a salvation that bringeth no regret." For what is admirable in it is this that one who had thus sorrowed would never repent, whilst this is an especial characteristic of worldly sorrow. For what is more regretted than a true born son? And what is a heavier grief than a death of this sort? But yet those fathers who in the height of their grief culture nobody and who wildly beat themselves, after a time repent because they have grieved immoderately; as having thereby nothing benefitted themselves, but even added to their affliction. But not such as this is godly sorrow; but it possesseth two advantages, that of not being condemned in that a man grieves for, and that this sorrow endeth in salvation; of both which that is deprived. For they both sorrow unto harm and after they have sorrowed vehemently condemn themselves, bringing forth this greatest token of having done it unto harm. But godly sorrow is the reverse [of this]: wherefore also he said, "worketh repentance unto salvation, a repentance that bringeth no regret." For no one will condemn himself if he have sorrowed for sin, if he have mourned and afflicted himself.