The church has always struggled to make sense of what the climax of Jesus' vocation and ministry on the Cross achieved and what it truly represents. The Letter to the Colossians puts this atoning work of Jesus in cosmic terms.
For in him all the fulness of God was pleased to dwell, and through him God was pleased to reconcile to himself all things, whether on earth or in heaven, by making peace through the blood of his cross. (Colossians 1.20).The struggle to understand exactly how this was achieved, is where the controversies arise. Different theories of the atonement have foundations in scripture, but each has been developed and described through the centuries. The most recent controversy concerns the theory of substitutionary atonement, in which the cross involves Jesus suffering the punishment for sin which was rightly ours.
Opponents of a narrow theory of substitution have claimed that it interprets God as vindictive, even cruel. Proponents have pointed to clear scriptural foundations (in Isaiah 53.4 and elsewhere) and to the fact that love demands justice, and justice punishment. The suffering of God in the person of Jesus is the action of a loving Trinity, not a vengeful tyrant.
Now this blog is no place for a lengthy exposition of scripture or examination of the development of doctrine. Even if I were capable (which I'm not), I would not think it worthwhile for most of us to get bogged down in theological subtleties. Sadly, as with debates about the incarnation, or arguments about the real presence of Christ in the eucharist, these controversies lead us up blind alleys. Forgetting the truth of the grace of God, to which these glorious doctrines bear witness, leads to strident and unloving battles for the victory of one theory over another.
Perhaps there is a wisdom in not seeking mechanisms for grace. Do we need to know the answer to all our 'how?' questions in order to embrace the truths of God's loving purpose? I think not. The quest for a mechanism leads to a kind of reductionism, that ultimately reduces God, his person and his purpose, to mere facts that can be conquered by human intellect. There is no mechanism for grace, except that it is to be received, with open and thankful hearts.