Is God Virtuous? Just and Merciful?

Summa Theologia I, Q21, a1 and a3, and SCG I.92
 
Some recent authors (including, I believe, Brian Davies and David Bentley Hart) have argued that God (as described in classical theism, including Thomism) is not a “moral being,” and so it makes no sense for us to find moral fault with God, as do those who press the problem of evil. Thomas addresses this question in Question 21 of the First Part. Thomas insists that God can be spoken of within the moral universe of discourse, since He can truly be said to have the moral virtues of justice and mercy.
 
In the case of justice, there are two forms: commutative and distributive. Commutative justice has to do with fairness in exchange, as in buying or selling. Distributive justice applies to one who distributes rewards or honors—the just distributor distributes them according to merit. Commutative justice does not apply to God, since no one could ever put God in his debt. However, God is clearly just in the distributive sense.
 
God also has mercy. Mercy consists in the virtue of one who dispels the miseries and defects of others. This God certainly does, since He is perfect goodness and goodness is (as we’ve seen) naturally dispersive. God is disposed to confer goodness on all of His creatures, including those most in need of this goodness to correct their defects. Hence, He is merciful.