I've been thinking for a little while about two related arguments for compatibilism about free will and predetermination based on Christian theology. In this post, I'll look at the implications of the traditional approach to the Incarnation, and in a second post I'll look at what the kind of robust view of inspiration that I favor will require. I'm cross-posting this at Prosblogion.
It seems to me that with the traditional understanding of the Incarnation, something like compatibilism must be true of Jesus' freedom. The traditional view of the Incarnation is that Jesus is fully God and fully human, and his divine nature prevents him from doing anything sinful, but at least in his earthly life he had all the human ability to do so, being fully tempted in every way. This means that we need some sense in which it's possible that Jesus do something wrong and some sense in which it's not. The best way I know of that anyone has captured this is to say that it was possible for Jesus to do wrong in relation to his human nature but not possible in relation to his divine nature.
But what does that mean? You might think it's natural to conclude that if two natures constrain him, and one allows it while the other doesn't, then it just implies that it's not possible for him to have sinned. His human nature would have allowed it, but the divine nature prevented it. But this seems just like the situation for someone with no legs: it's possible for them to walk with respect to their brain but not possible for them to walk with respect to their legs. So it's simply just not possible for them to walk, unless it's ever proper to ignore the obstacle sufficient for preventing that possibility. But it pretty much never is proper to ignore that obs tacle unless you're talking about attaching new legs or something like that. But there's no such analogous possibility with Jesus, as if he could lose his divine nature. So this doesn't well capture the intuition that there's some sense in which Jesus could have sinned, in order to explain the statements about his having been genuinely tempted. This complaint strikes me as much like the complaint that libertarians on free will offer against compatibilism.
If the causes of our actions can be traced back to events outside our control, then incompatibilists will claim that we are not free. They will say that there's no possibility that things will be otherwise. A certain variety of compatibilist, however, will say that there's a sense in which it's not possible and a sense in which it's possible. It's possible with respect to the factors that we usually care about when we consider ourselves free, but it's impossible with respect to the actual past and laws of nature. When we are concerned with our freedom, what we care about is the fact that we consider options, evaluate them based on our own desires and motivations, and act in such a way that our decision-making process is what leads to our eventual choice. If that process can include options to be considered that are not possible in the broader sense, we still call them possibilities in ordinary discourse, because we're restricting ourselves to a more limited sense of what it means to be possible. We can consider it a live option.