The doctrine of purgatory is naturally associated with Roman Catholic theology, but some Protestant philosophers and theologians affirm the doctrine (albeit a version of the view which sees purgatory as serving the function of completing sanctification rather than providing final satisfaction for sin). One of the most prominent of these is Jerry Walls, who has published a trilogy of Oxford monographs on personal eschatology, as well as Heaven, Hell, and Purgatory, a single volume treatment of the subject.
Walls, who is a Wesleyan, defends the doctrine of purgatory beginning with the basic idea that salvation is not just about forgiveness of sins but is mainly about spiritual transformation. So if salvation essentially involves transformation, “what becomes of those who plead the atonement of Christ for salvation but die before they have
been thoroughly transformed?” Such people, he says, “do not seem ready for a heaven of perfect love and fellowship with God, but neither should they be consigned to hell.” The standard Protestant view is that for such people full sanctification is accomplished immediately and painlessly “by a unilateral act of God at death.” This view, which some scholars call “provisionism” is deeply problematic, according to Walls. One of his arguments appeals to human temporality. Since all human moral growth and maturation on earth is a process that takes time, then it makes sense to assume that our moral progress in the next world will be a temporal process. This suggests something like a purgatorial completion of our sanctification. Walls also uses an argument from human freedom. The idea here is that all human sanctification on earth involves free human choices as we cooperate in the process of moral growth. A unilateral act of God that instantaneously perfects us would be a radical departure from this basic aspect of our experience.
Another Protestant advocate of purgatory is philosopher Justin Barnard. In his Faith and Philosophy article “Purgatory and the Dilemma of Sanctification,” Barnard emphasizes two further considerations. One of these is the problem of personal identity that provisionists face. With such a radical sudden transformation of one’s moral nature, as provisionists propose, how can one be properly considered the same person afterwards? Preservation of personal identity through time requires more gradual change, Barnard would say, and this suggests a slow purgatorial transformation.
But Barnard’s primary concern regards the problem of evil. If God can perfect us morally suddenly after death, then why doesn’t he do it now? The fact that God waits suggests that there is a lot of evil that God cannot remove “without thereby sacrificing any significant good.” Here some appeal to the idea that God refrains from perfecting us on earth in order to respect our free will. But then this implies that God takes away our freedom when he perfects us in heaven. But if that’s not problematic in heaven, then why would it be problematic here? Barnard proposes that the doctrine of purgatory—or his “sanctification” version of the doctrine anyway—avoids this problem, as it says that the process of moral perfection that we begin on earth is simply completed in the afterlife—gradually and eventually completely.
Personally, I am not a proponent of the doctrine of purgatory, but I must admit that such arguments give me pause. While they might never ultimately persuade me to accept the doctrine, I certainly respect the view and see why it has been affirmed by so many great Christian thinkers down through history.