That could be done in a new thread. For the time being, let’s take two, simple attributes: “just” and “merciful”. A just judge would deliver a sentence, which is exactly, precisely commensurate to the deed. A merciful judge would deliver a sentence that is more lenient than what would be deserved.
Mercy doesn’t contradict justice, rather, it is better said that mercy goes beyond justice. Justice says that the criminal owes this to God for his sins, but God says that I give you that which you owe me as gift.
St. Thomas uses this analogy:
God acts mercifully, not indeed by going against His justice, but by doing something more than justice; thus a man who pays another two hundred pieces of money, though owing him only one hundred, does nothing against justice, but acts liberally or mercifully. The case is the same with one who pardons an offence committed against him, for in remitting it he may be said to bestow a gift. Hence the Apostle calls remission a forgiving: “Forgive one another, as Christ has forgiven you” (Ephesians 4:32). Hence it is clear that mercy does not destroy justice, but in a sense is the fulness thereof. And thus it is said: “Mercy exalteth itself above judgment” (James 2:13).
So, in other words, the criminal gives what is owed to God, to God, and God simply gives it back to him as free gift. The gift by definition is not owed to the criminal, but is give to him because of the goodness and mercy of God.
(There would be a third alternative, a “hanging judge”, whose sentence is more severe than deserved. That would be God, if there would be a hell.)
Just as God has deemed that temporary actions can receive eternal reward, it follows that temporary actions can fairly receive eternal damnation too. If goodness can merit eternal life, then a lack of goodness can fairly merit a lack of eternal life: eternal death, or hell.
Furthermore, those who do harm against someone in authority receive a greater punishment, like how a man who kills a police officer is punished more severely. In a similar way, since God’s glory is infinite, an infinite punishment of doing wrong against him is just.
St. John of the Cross says that we will be judged on our love. Our offense to our neighbor is bad enough, but to see our offense to the infinite God who is loving us with infinite love our whole lives is way too much to bear. I think you should read this article by Mr. James Chestek:
thomism.wordpress.com/2010/01/21/to-be-judged-on-love/
By willing against charity, a man cuts himself off from the City of God, as St. Augustine puts it, since charity is the “glue” that holds God and the Blessed together. Therefore, he who acts against charity makes him unfit to live in the New Jerusalem, just as a murder makes himself unfit to live in our communities, and so we jail him. If the criminal shows sorrow and repentance for his actions, after a while he may be allowed to re-enter the community, as in our institution of justice, and as in those in purgatory. But for those who will sin, unless their will begins to reform into one of charity, they will always will sin, they will always will their final end to be a creature, and so God exiles them from the City of God and allows him to experience the true nature of his sin, as we see in Dante’s
Inferno.
The man who wants to stop sinning just because of his punishment is not repentant, because he would still continue in the sin if there was no punishment. His will is still in conflict with God. While as someone in purgatory understands the evil of his sin, and in some degree no longer will sin, and the time in purgatory helps fully rectify his will, free it from the enslavement of sins and disordered emotions, ordering his passions to their proper objects, and integrate his will with his passions into a unity. In other words, purgatory helps develop virtue so that man can be a master of himself, so that that love of God and neighbor that was suppressed under disordered passions and an enstrangled will can be overcome and expressed in pleasure and joy to the fullness in the Kingdom of Heaven, as we see at the end of Dante’s journey to the top of Mt. Purgatory:
*When all the staircase lay beneath us and
we’d reached the highest step, then Virgil set
his eyes insistently on me and said:
'My son, you’ve seen the temporary fire
and the eternal fire; you have reached
the place past which my powers cannot see.
I’ve brought you here through intellect and art;
from now on, let your pleasure be your guide;
you’re past the steep and past the narrow paths.
Look at the sun that shines upon your brow;
look at the grasses, flowers, and the shrubs
born here, spontaneously, of the earth.
Among them, you can rest or walk until
the coming of the glad and lovely eyes—
those eyes that, weeping, sent me to your side.
Await no further word or sign from me:
your will is free, erect, and whole—to act
against that will would be to err: therefore
I crown and miter you over yourself.’*
An unrepentant sinner acts against his own self-mastery, and doesn’t possess any love of God, and so the fires cannot purify him, for there is nothing in him to bring out and purify, no love of God. No matter how much you try, you can’t bring gold out of an ore that doesn’t possess any.