In the last year or so, it seems like I’ve read more books than ever that speak about God suffering at the cross. Chris Braun’s book Unpacking Forgiveness is otherwise excellent, but even he speaks in this vein: our forgiveness “was purchased at the price of the shed blood of God himself” (47). Reading Jaroslav Pelikan’s The Emergence of the Catholic Tradition (100-600) this afternoon reminded me that this was a hotly debated issue in the early church. But eventually it also became a settled issue. He suffered and died in his human nature, experiencing the wrath of God in so doing. This he was able to do by virtue of his divine nature. But the blood shed on Calvary was not divine. It was pure human blood and so it had to be.
Heidelberg Catechism QA 17
Q. Why must he at the same time be true God?
A. He must be true God so that by the power of his divine nature he might bear in his human nature the burden of God’s wrath and might obtain for us and restore to us righteousness and life.