Free will is used in these debates because the vision of God torturing people for all eternity raises a host of snarly problems related to the goodness of God. But if the responsibility for the persistence of our separation from God could be shifted away from God and onto human choice--the door of hell is locked from the inside--some of the moral concerns about hell attenuate. We, and not God, are to blame for this predicament.
Yesterday, I pointed out how free will is doing a lot of heavy lifting in these debates. Maybe free will can carry that theological load. My point is that it's an odd and precarious sort of theological system that wholly depends upon a speculative and controversial account of human psychology.
Today, though, I want to turn to the plausibility of a human will eternally rejecting God.
Again, a premise of this debate is post-mortem movement, like what C.S. Lewis imaginatively describes in The Great Divorce. In that novel, the denizens of hell can take a bus ride to heaven. Upon arrival, some, like the narrator of the story, want to stay and are willing to undergo the purification necessary to remain. There's a hint of Dante's Purgatorio here. Other bus riders experience heaven with loathing and return to hell. Some for all eternity.
This vision of post-mortem opportunity and movement isn't a common view, but it is espoused by many to defend eternal separation from God against universalist attacks against the moral coherence of that vision. Many consider the moral argument against hell to be universalism's strongest selling point. So the free will defense, that our separation from God is self-imposed, is used to rebut that argument. God is willing to have us, but we refuse.
Something to point out here is that both the free will defenders and the universalists have a lot in common. For example, by embracing a vision of post-mortem movement, both groups are swimming in some pretty heterodox waters. Both groups also believe in hell, though the visions here range from self-inflicted suffering to a refining purgation. The critical difference, though, concerns if it is possible for the human will to resist God forever.
Again, this is a niche debate, so you have to assume the parameters of the argument, which a lot of Christians reject. But here's a simple sketch of the thought experiment:
1. Upon their death, unsaved and unrepentant souls (let's call them rebels) go to hell.
2. Although in hell, rebels are not separated from God's gracious, saving actions. There is the post-mortem possibility of the rebels turning to God.
3. While some rebels will come to God, other rebels will resist for all eternity. Eternal separation is a possibility, but that separation is not God's doing but due to the intransigence of the rebels. The exile is self-imposed. (This is the vision of C.S. Lewis' The Great Divorce.)
Okay, even if you disagree with all this, for the sake the thought experiment we can focus on the debate between the free will defenders of eternal separation and the universalists. The critical issue is this: Can the human will resist God forever, especially if God is actively pursuing that person? Can the human will resist God's active grace for all of eternity?
If you believe in the free will defense of eternal separation, your answer is "yes," a rebel can remain a rebel for all eternity. For the universalist, the answer is "no," the human will cannot resist God forever and will, eventually, turn toward the light.
Let me restate the curiosity here, how much this debate hangs upon very some speculative accounts of what free will can and cannot do in the face of God's grace. Seriously, a very speculative psychological question--Can the human will resist God's grace for all eternity?--is the very point of contention. Some say yes, and some say no. But how could you even adjudicate between those answers beyond, "I find X plausible" versus "I find X implausible"? At root, we have a conflict here between competing intuitions about human freedom. Some think rebels can remain rebels forever. This seems to them to be a wholly realistic possibility. Universalists, by contrast, disagree. They feel that it's totally unrealistic to think that a human person could resist God for all eternity. Eternity being, well, a very long time and God being, well, God. God will eventually get what God wants.
To be sure, arguments are made here. Defenders of eternal separation defend it because they feel Scripture commits them to the word "eternal" (under a particular definition of that word, as being a quantitative rather than a qualitative distinction). So even if their view of free will is speculative and implausible, they are committed to it in order preserve what they feel is an orthodox commitment to eternal separation, with emphasis on the word "eternal" (quantitatively understood). A modern and speculative psychology, unknown to the biblical writers, is embraced to defend a traditional belief. This is an ironic and strange thing to do, grounding traditional theology in modern psychology, but free will defenders of hell do it nonetheless.
Universalists make their arguments, arguing that a finite will cannot win a conflict with Infinite Love, especially if the timeframe is all eternity. The Hound of Heaven will eventually chase you down. God is infinitely kind, patient, and resourceful.