The Enchiridion

Thus, then, matters stood. The whole mass of the human race was under condemnation, was lying steeped and wallowing in misery, and was being tossed from one form of evil to another, and, having joined the faction of the fallen angels, was paying the well-merited penalty of that impious rebellion. For whatever the wicked freely do through blind and unbridled lust, and whatever they suffer against their will in the way of open punishment, this all evidently pertains to the just wrath of God.

But the goodness of the Creator never fails either to supply life and vital power to the wicked angels (without which their existence would soon come to an end); or, in the case of mankind, who spring from a condemned and corrupt stock, to impart form and life to their seed, to fashion their members, and through the various seasons of their life, and in the different parts of the earth, to quicken their senses, and bestow upon them the nourishment they need. For He judged it better to bring good out of evil, than not to permit any evil to exist.

And if He had determined that in the case of men, as in the case of the fallen angels, there should be no restoration to happiness, would it not have been quite just, that the being who rebelled against God, who in the abuse of his freedom spurned and transgressed the command of his Creator when he could so easily have kept it, who defaced in himself the image of his Creator by stubbornly turning away from His light, who by an evil use of his free-will broke away from his wholesome bondage to the Creator's laws—would it not have been just that such a being should have been wholly and to all eternity deserted by God, and left to suffer the everlasting punishment he had so richly earned?

Certainly so God would have done, had He been only just and not also merciful, and had He not designed that His unmerited mercy should shine forth the more brightly in contrast with the unworthiness of its objects.