Punishment is nowise an offset to sin. Punishment, deserved suffering, is no equipoise to sin. Suffering weighs nothing at all against sin. If sin sits on one scale, it will move it not a hairsbreadth to lay punishment and suffering on the other. They are not of the same kind, not under the same laws, any more than mind and matter. To attempt to equate them would be like placing a cubic inch of lead on the one scale, and attempting to balance it by placing a cubic yard of air on the other. The sin is unmoved. It remains where it is though an eternity of punishment and suffering be brought to bear against it.
If it were an offset to wrong, then God would be bound to punish for the sake of punishment. But he cannot be, for he forgives. Then it is not for the sake of punishment, as a thing that in itself ought to be done, but for the sake of something else, as a means to an end, that God punishes.
Primarily, God is not bound to punish sin; he is bound to destroy sin. If he were not the Maker, he might not be bound to destroy sin — I do not know. But seeing he has created creatures who have sinned, and therefore sin has, by the creating act of God, come into the world, God is, in his own righteousness, bound to destroy sin.
— George MacDonald, Unspoken Sermons, Third Series, “Justice,” quoted in Discovering the Character of God</em>, compiled by Michael Phillips, p. 258