How to Explain Purgatory to Protestants
by James Akin
Suppose a friend or co-worker comes to you and says:
"The Catholic Church has this massive doctrine of purgatory, invented in the middle ages. The Church used to even sell indulgences to shorten your time in purgatory by a fixed number of days. This doctrine is based on books that don't belong in the Bible. There is no place or region in the afterlife for the saved except heaven. There is no pain in the afterlife, and the minute we die we go to heaven, as Paul says, 'To be absent from the body is to be present with Christ,' praying for people in purgatory makes no sense. Worst of all, it infringes on the sufficiency of Christ's work. It is completely unbiblical. No Protestant could believe it."
What should you say?
Well, the first thing you should say is, "Whoa! Slow down! One argument at a time, okay?" Then go over his arguments with him individually . . .
1. "The Catholic Church has this massive doctrine of purgatory."
This is quite false. As an illustration of this, the section on purgatory in the Catechism of the Catholic Church is only three paragraphs long (CCC 1030-1032). In essence, there are only three points on the matter which the Catholic Church insists: (1) that there is a purification after death, (2) that this purification involves some kind of pain or discomfort, and (3) that God assists those in this purification in response to the actions of the living. Among the things the Church does not insist on are the ideas that purgatory is a place or that it takes time, as we shall see below.
2. "Invented in the middle ages."
The idea that purgatory is a late invention is similarly false. In fact, it has been part of the true religion since before the time of Christ. It is witnessed to not only in such as 2 Maccabees, which itself witnesses to the belief (see below), but in other pre-Christian Jewish books as well, such as The Life of Adam and Eve, which speaks of Adam being freed from purgatory on the Last Day.
It was also part of the true religion in Jesus' day, as the writings of the New Testament show. And it has been part of the true religion ever since Christ's day, as the writings of the Church Fathers show (see the Catholic Answers pamphlet: "The Fathers Know Best: Purgatory").
Not only Catholics believe in this final purification, but the Eastern Orthodox do as well (though they often do not use the term "purgatory" for it), as do Orthodox Jews. In fact, to this day, when a Jewish person's loved one dies, he prays a prayer known as the Mourner's Qaddish for eleven months after the death for the loved one's purification.
Because the doctrine of purgatory was held by pre-Christian Jews, post-Christian Jews, Catholics, and Eastern Orthodox, nobody thought of denying it until the Protestant Reformation, and thus only Protestants deny it today.
3. "The Church used to even sell indulgences to shorten your time in purgatory by a fixed number of days."
Concerning this argument, first point out that it really deals with the issue of indulgences, which is a separate matter (see my piece, "A Primer on Indulgences"). If one wishes to really hear what Catholics have to say for themselves, one subject must be dealt with at a time, not several at once in some kind of "buckshot" approach to apologetics.
Second, indulgences were never sold. At one time, for a period of perhaps two hundred years, it was possible to give a charitable donation to some cause, such as an orphanage or church building fund, asone of the ways in which an indulgence could be obtained. This was no different than Protestant ministries offering something in exchange for a charitable contribution or "love offering" to a worthy cause. However, because of the scandal that Protestants produced, over four hundred years ago (shortly after the Council of Trent) the Church forbade charitable giving as a way of obtaining indulgences.
Third, Protestants are often confused by the number of "days" that used to be attached to indulgences. They have nothing to do with time in purgatory. Indulgences originally arose as a way of shortening a penitential period on earth. The number of "days" that were attached to indulgences were not understood as shortening time in purgatory, but as easing the purification after death by an amount analogous to the shortening of an earthly penitential period by the number of days indicated.
Fourth, because some people were confused by thinking purgatory was shortened by a set number of days with an indulgence, the Church abolished the "day" figures attached to indulgences specifically to eliminate this confusion.
Fifth, the reason that the "days" were never understood to be days of literal time off in purgatory is that the medieval theologians, such as St. Thomas Aquinas, those living at precisely the period when they "days" were attached to indulgences, were very clear about the fact that time does not work the same way in the afterlife as it does here. In fact, they had a special term for it, and would contrast three different temporal modalities -- the ordinary flow of events we experience here on earth, called "time;" the perpetual present that God experiences, called "eternity;" and the middle, less well understood state experienced by those in the afterlife, known as "aeviternity."
So the Church has never said that purgatory involves the same kind of time as we experience here on earth, or even time at all. Thus Cardinal Joseph Ratzinger, no theological liberal, writes that purgatory may involve "existential" rather than "temporal" duration (cf. Ratzinger's book Eschatology). It may be someone one experiences, but experiences in a moment, rather than something one endures over time.
4. "This doctrine is based on books that don't belong in the Bible."
When a Protestant says this, he has in mind 2 Maccabees 12, in which Judah Maccabee and his men pray for their fallen comrades who had "fallen asleep in righteousness" so that they may be "freed from their sins" in the afterlife, and it was a "holy and pious thought" for them to do this.
Thus 2 Maccabees endorses praying for the dead that they may be loosed from the consequences of their sins (for it must be the consequences of sin that are in mind since the saved are not sinning in the afterlife). Since it is not pleasant to be bound to the consequences of one's sins, we can infer some kind of pain or discomfort, and thus the full doctrine of purgatory -- a purification (freeing) after death, which involves some kind of pain or discomfort, and which can be assisted by the prayers of the living.
However, while 2 Maccabees 12 certainly teaches the doctrine of purgatory, the doctrine is in no way "based on" that passage. The doctrine can also be supported from numerous passages in the New Testament, but more fundamentally (and this is what you should point out to the Protestant), it can be derived from the principles of Protestant theology alone.
You see, Protestant are very firm (in fact, insistent) about the fact that we continue sinning until the end of this life because of our corrupt nature. However, they are equally firm (if you press them) about the fact that we will not be sinning in heaven because we will no longer have a corrupt nature. Thus between death and glory there must be a sanctification -- a purification -- of our natures.
This purification may take no time, but as we have seen, this is no barrier to the doctrine of purgatory. The fact remains that between death and glory must come purification, and that is purgatory by definition -- the final purification or, to put it in more Protestant terms, "the final sanctification" or "the last rush of sanctification."
5. There is no place or region in the afterlife for the saved except heaven.
Well, this may be true. The Church teaches that purgatory is the final purification, but not that it occurs in any special region in the afterlife. Just as we do not know how time works in the afterlife -- meaning that purgatory may take no time -- we also do not know how space works in the afterlife, especially for unembodied souls -- meaning purgatory may not take place in any special location.
The final purification may take place in the immediate presence of God (to the extent that God's presence may be described in spatial terms). In fact, in his book on eschatology, Cardinal Joseph Ratzinger describes purgatory as a fiery, transforming encounter with Christ and his love:
"Purgatory is not, as Tertullian thought, some kind of supra-worldly concentration camp where one is forced to undergo punishments in a more or less arbitrary fashion. Rather it is the inwardly necessary process of transformation in which a person becomes capable of Christ, capable of God [i.e., capable of full unity with Christ and God] and thus capable of unity with the whole communion of saints. Simply to look at people with any degree of realism at all is to grasp the necessity of such a process. It does not replace grace by works, but allows the former to achieve its full victory precisely as grace. What actually saves is the full assent of faith. But in most of us, that basic option is buried under a great deal of wood, hay and straw. Only with difficulty can it peer out from behind the latticework of an egoism we are powerless to pull down with our own hands. Man is the recipient of the divine mercy, yet this does not exonerate him from the need to be transformed. Encounter with the Lord is this transformation. It is the fire that burns away our dross and re-forms us to be vessels of eternal joy."
Thus according to Ratzinger's way of explaining the doctrine, as we are drawn out of this life and into direct union with Jesus, his fiery love and holiness burns away all the dross and impurities in our souls and makes us fit for life in the glorious, overwhelming light of God's presence and holiness.
6. "There is no pain in the afterlife."
Now this argument is quite false. It is not true that there is no pain in the afterlife, even for the saved. We are told that one day, in the eternal order, "he will wipe away every tear from their eyes, and death shall be no more, neither shall there be mourning nor crying nor pain any more, for the former things have passed away" (Revelation 21:4) -- but note when this happens: in the eternal order, after the descent of the New Jerusalem and the passing away of the current heaven and earth.
Before that time, Scripture gives us no promise that we will be free of all pain. In fact, it indicates quite the opposite. Paul tells us:
"[W]hether we are at home or away, we make it our aim to please him. For we must all appear before the judgment seat of Christ, so that each one may receive good or evil, according to what he has done in the body. Therefore, knowing the fear of the Lord, we persuade men" (2 Corinthians 5:9-11).
Paul states that out of the fear of the Lord he tries to please God because we will all stand before God to be judged by whether what we have done is good or evil. Thus the prospect of appearing before Christ's judgment seat is a fearful thing, even for the Christian.
This is something recognized even by Protestants. For example, in his Through The Bible series (on Romans 14 in this case), Protestant preacher J. Vernon McGee commented that he was not looking forward to the judgment seat of Christ, because at his judgment seat Jesus Christ was going to take J. Vernon McGee apart, which is certainly something that Christ endorses, saying to his disciples (Christians):
"Nothing is covered up that will not be revealed, or hidden that will not be known. Therefore whatever you have said in the dark shall be heard in the light, and what you have whispered in private rooms shall be proclaimed upon the housetops. I tell you, my friends, do not fear those who kill the body, and after that have no more that they can do. But I will warn you whom to fear: fear him who, after he has killed, has power to cast into hell; yes, I tell you, fear him!" (Luke 12:2-5)
So according to both Jesus and Paul we have reason to fear the unstoppable, unavoidable, unrelenting, and microscopic examination to which our lives will be subjected when we stand before Jesus. We must not have an unreasonable, unhealthy fear of this, the kind which leads to despair, but we must have the healthy, Godly fear which Paul and Jesus counsel.
The painful loss which even the righteous will experience in the afterlife is brought forward with especial clarity in 1 Corinthians, where Paul tells us:
"Now if any one builds on the foundation with gold, silver, precious stones, wood, hay, straw, each man's work will become manifest; for the day will disclose it, because it will be revealed with fire, and the fire will test what sort of work each one has done. If the work which any man has built on the foundation survives, he will receive a reward. If any man's work is burned up, he will suffer loss, though he himself will be saved, but only as through fire" (1 Corinthians 3:12-15).
This clearly applies to the saved, for Paul says so ("he himself will be saved"), but it does not indicates that this life-review will be fun, for Paul also says, the person in question's work "is burned up" and "he will suffer loss" and though he will be saved, it will be "only as through fire." Needless to say, seeing ones life's work go up in flames, suffering loss when one was expecting to "receive a reward" and escaping through the flames is not fun.
Thus the day on which we receive our particular judgment at the end of life will not be fun to the extent our works are not good. This clearly shows the reality of pain and discomfort after death but before the inauguration of the eternal order.
Now some Protestants try a dodge to get around this passage by saying that it is our works which are tested. It is true that on the surface of this passage. Paul does say our works will be tested by fire. However, this changes nothing since we will existentially feel it as our works are tested and consumed. That is why Paul says one whose works survive will "receive a reward" -- something he will feel -- and one whose works are consumed will suffer loss -- again, something he will feel.
Thus Paul caps the passage by saying that the saved one who suffers loss will be saved "only as through fire" -- the image being that of a man escaping from a burning building, which is precisely what Paul was talking about -- the local church as a building built by men either with fire-proof materials or materials which will be consumed (read the prior context). Thus the picture is of a man having built up his local church improperly, then seeing his work -- the building he has built -- consumed by fire, so he has to flee from it amid the flames to escape.
Thus while Paul says our works (the building we do) will be tested by fire, he envisions the flames touching us ourselves if our building ignites and we are forced to flee from it. So while under this metaphor in Paul our works are tested, we ourselves feel the consequences of this testing in the most painful way possible, for it is no fun to have to escape from a burning building as the work of your life comes crashing down around you.
7. "Paul says, 'To be absent from the body is to be present with Christ.'"
This is virtually the mantra of some Protestant radio personalities. However, it is totally and completely false. Paul did not say, "To be absent from the body is to be present with Christ." What he actually said was this:
"6 So we are always of good courage; we know that while we are at home in the body we are away from the Lord, 7 for we walk by faith, not by sight. 8 We are of good courage, and we would rather be away from the body and at home with the Lord. 9 So whether we are at home or away, we make it our aim to please him. 10 For we must all appear before the judgment seat of Christ, so that each one may receive good or evil, according to what he has done in the body. 11 Therefore, knowing the fear of the Lord, we persuade men; but what we are is known to God, and I hope it is known also to your conscience" (2 Corinthians 5:6-11).
Notice that Paul is speaking of himself with the plural "we" in this passage, as he shows in verse 11, mentioning his evangelizing ministry and contrasting the "we" who persuade men and are known to God, with the hope that "your conscience" also has the same view of us. His words clearly have application to other people in principal, but he is speaking primarily of himself.
So what Paul says here is (v. 6) that he knows while he is in the body he is away from the Lord, which is certainly something that is true and which no Catholic would deny. We are not in the immediate, unmasked, visible presence of Christ in this life. So to this verse, a Catholic can simply say, "So what? Who does not know these things?"
Paul then states (v. 8) that he would rather be away from the body and at home with the Lord. This is the one which Protestant radio personalities slur into "to be absent from the body is to be present with Christ." That is not what Paul said.
First of all, he is speaking concerning himself, remember, not concerning people in general. There are quite a lot of Christians, and to be frank, it is the majority of them, who would much rather be present in the body than die and go to be with Jesus. Paul's preference for death to be with Jesus over life to stay in the body is nothing like a universal sentiment among Christians.
Second, he is expressing a desire. He desires something to happen. But there is a big difference between saying that one want's something to happen and that it will infallibly happen.
Third, there is an even bigger difference between saying one wants two things to happen and to say that when one happens the other will happen instantaneously. For example, if I as a single person said, "I want to go home and eat dinner," I would not mean that the instant I go home I will be eating dinner. Since I am a single person, before I can eat dinner I have to make dinner. There is obviously some time lag between my home-going and my dinner-eating. The same would can be said in the case of a person who says, "I want to go home and watch my favorite program." When one goes home, that does not mean one is instantaneously watching one's favorite program. In fact, it may be hours before one's favorite program comes on.
And notice that in the parable of Lazarus and the Rich Man Jesus pictures the dead soul as being carried by angels to his place of rest (Luke 16:22). Obviously, under this image, some transport time is pictured.
Fourth, it also does not follow, even if one thing automatically follows from another that the two are identical. If B follows from A, it does not warrant the statement that A is B, yet this is precisely the way in which Protestant radio personalities warp Paul's language when they declare, "Paul says, 'To be absent from the body is to be present with the Lord.'" They say this in such a way that it sounds like a direct quote, not a summary, and because many people never look up the verse to see what Paul actually says, they never realize that it isn't a direct quote, and so they are misled into thinking Scripture says something it does not.
Thus this (inaccurate) summary of Paul's language has passed into the realm of myth. It is one of those mythical verses that people have heard so often they think the Bible says it even though it actually doesn't (for example, "Spare the rod and spoil the child," "The lion shall lie down with the lamb," (among Pentecostals:) "Speaking in tongues is the evidence of baptism in the Holy Ghost," and the king of all mythical verses: "He helps those who help themselves"). The Protestant radio personalities thus contribute not only to the Biblical illiteracy of society in saying this, but to the Biblical mis-literacy.
Fifth, it is especially ironic that this passage is used to disprove purgatory since it speaks (vv. 9, 10, 11) of the need to please the Lord in this life because when we are absent from the body and present with the Lord we will have to "appear before the judgment seat of Christ" to give an account of everything we have done in our life in the body, which Paul says motivates him since he is one "knowing the fear of the Lord." So one can say, "You want to be absent from the body and instantaneously present with Christ? Fine! Good for you! But what is going to happen when you are absent from the body and present with Christ -- as this very passage shows -- is the particular judgment, at which you will give an account of every one of your deeds and your works will be tested by fire."
In any event, the first thing you should point out to a Protestant who uses the "absent from the body/present with Jesus" canard is: "That's not what Paul said. What he actually said is that he 'would rather be away from the body and at home with the Lord.' But there is a huge gulf between the statement 'I desire to A and to B' and the statement 'Everyone who does A will instantaneously do B,' much less the statement 'To A is to B'!"
The second thing you should point out is this: "Hey! Remember: Purgatory may be instantaneous! So even if we were instantaneously in Christ's presence after death (contrary to Christ's illustration of being carried by angels to our destiny), so what? That doesn't make one whit of difference to the Catholic position since time does not work the same way in the after life and purgatory may simply be an instantaneous 'in the twinkling of an eye' transformation."
8. "Praying for people in purgatory makes no sense."
One thing Protestants often have a hard time understanding, especially if they are aware of the fact that purgatory may take no time, is the practice of praying for those being sanctified. They will ask, "If one has died and the time of finding forgiveness is over, how can praying make any difference? And if one's purification takes no time, how can you pray for it after the fact?"
In answer to the first question, remember what purgatory is: The final stage of sanctification. Now sanctification can be painful or non-painful (usually the former), including the its final stage. So just as we may pray for others in this life to be made holy more quickly or in a non-painful way, so we may pray for those in the final stage of sanctification to be made holy more quickly or in a non-painful way.
Consider an analogy: Suppose you have a friend who goes to join the army and is in bootcamp. Now (theoretically) everyone who enters the army must be brought up to a certain level of physical excellence, which is the purpose of bootcamp. It doesn't matter where you start from, bootcamp's purpose is to bring you up to that level of physical excellence.
This is what purgatory does. Purgatory is the bootcamp of heaven. The purpose of purgatory is to bring you up the level of spiritual excellence needed to experience the full-force presence of God. It doesn't matter where you start from, there will be no sinning in heaven, and you have to be brought up to that level during final sanctification, before you are glorified with God in heaven.
Now when you have a friend in bootcamp, whether a physical bootcamp here on earth or the spiritual bootcamp in the afterlife, you can pray for him that bootcamp will go easier on him, that he will brought up to the level of excellence he needs in the most painless way possible. It may or may not shorten his time in bootcamp (in fact, in the U.S. Army bootcamp is of a fixed length), but you can still pray that it will go easier on him as he is brought to where he needs to be.
In regard to the second question, how we can pray for someone if their purification was instantaneous, this is no different than praying for any past event. God is outside of time and so knows your request from all eternity, meaning he can apply your request to whatever period in time it is relevant to.
Thus many a Protestant minister, thinking of someone who has just died and whose profession of faith was doubtful, will say, "O Lord, if it is your will, may he have put his faith in your Son before he died!"
Similarly, many Protestant laity, when furiously rushing home because a terrible accident has happened and they are afraid someone, say their daughter, is dead, will pray, "O Lord, when I get there, may she not be dead! May she not be dead, O Lord!" Of course, either she is or she isn't. She has already died or not died. But it is still rational, because God is outside of time and hears all of our requests at once, to ask God to not have let something happen to her while we were gone.
C.S. Lewis, the well-known Protestant author, talks about prayer for past events quite extensively in his writings, and he makes the point that the only time it is irrational to pray for a past event is when oneknows that it was not God's will to answer the prayer because one already knows how the event came out. Thus it would be irrational to pray that Abraham Lincoln not be assassinated, since one already knows that he was, or it would be irrational to pray that the Nazis lose a particular battle in World War II if one already knows they won that battle. In those cases it is irrational to pray since one already knows the will of God on the matter and knows that it was not your will. But so long as one does not know what God's will is concerning something, whether it is past, present, or future, it is still rational to pray.
Thus if it turns out that purgatory is instantaneous at the point of death, it is still rational to pray that that final sanctification will have gone easier on those who experienced it, the same way it is rational for a Protestant minister at a funeral to pray in his heart, "O Lord, may this man have put his trust in your Son!"
9. "It infringes on the sufficiency of Christ's work."
Okay. The idea here is that since purgatory involves suffering, it must some how infringe on the sufferings of Christ and imply they weren't sufficient.
Remember: Purgatory is simply the last stage of sanctification. Sanctification in this life involves pain, for "For the Lord disciplines him whom he loves, and chastises every son whom he receives. . . . [And] For the moment all discipline seems painful rather than pleasant" (Hebrews 12:6, 11), yet no one says that suffering infringes on Christ's sufferings. In the same way, the suffering during the final sanctification in no way infringes on Christ's sufferings or implies they were insufficient.
Quite the contrary! The fact is that the suffering we experience in sanctification in this life is something we receive because of Christ's sacrifice for us. His sufferings paid the price for us to be sanctified, and his sufferings paid the price for the whole of our sanctification -- both the initial and final parts. Thus it is because of Christ's sacrifice that we receive the final sanctification in the first place! If he had not suffered, we would not be given the final sanctification (or the glorification to which it leads), but would go straight to hell. Thus purgatory does not imply Christ's sufferings were insufficient; rather it is because of Christ's sufferings that we are given the final sanctification of purgatory in the first place!
10. "It is completely unbiblical."
What we have said so far should reveal the falsity of this charge. Purgatory is in no way an unbiblical doctrine. Rather, it is completely biblical on both implicit and explicit grounds. Implicitly, it can be derived from the biblical principles that we still sin till death but that there will be no sin in glory. Thus between death and glorification must come purification.
Explicitly, we not only have the witness of passages such as 2 Maccabees 12, but also the witness of passages describing our accounting before Christ in the particular judgment, including the especially vivid depiction of one escaping through the flames in 1 Corinthians 3:11-15.
Jesus himself adds to this when he speaks in Matthew 12:32 of a sin which will neither be forgiven in this age nor the age to come, implying that some sins (venial ones of which we have not repented before death) will be forgiven when we repent the first moment of our afterlife.
Furthermore, in Matthew 5:25-26, Jesus tells us: "Make friends quickly with your accuser, while you are going with him to court, lest your accuser hand you over to the judge, and the judge to the guard, and you be put in prison; truly, I say to you, you will never get out till you have paid the last penny."
In this parable God is the Judge, and if we have not reconciled with our neighbors before we see God, God will hold us accountable for the wrong we did to them. This is what the Bible means when it says that God will take our revenge for us, so we should not take it ourselves, because God will defend the cause of the poor and uphold the case of the widow. Whenever a poor person or widow (or anyone else) is oppressed or wronged, God will hold the oppressor accountable for what he did -- unless the wronged person freely chooses to forgive the offender. In that case, God will not hold the offender accountable for the wrong he did on a human level (i.e., against the human he wronged), but unless he has obtained forgiveness from God for the wrong he did against God, he will still be held accountable for that.
Thus in our sins against others they are two dimensions -- the human, by which we sin against our neighbor in the act, and the divine, by which we sin against God in the act. Thus theft is a sin against our neighbor from whom we stole and a sin against God, whose law we broke. We must obtain forgiveness from God for the divine aspect of our sin, but, as Jesus tells us in Matthew 5:25-26, we must obtain forgiveness for the human aspect of our sin from the human we sinned against. If we do not, God will hold us accountable.
Of course, since humans are finite beings, our sins against them can only merit finite punishment (compared to our sins against God, who is an infinite being, so our sins against him can merit infinite punishment). Because this punishment is finite, it must be temporary (for an eternal punishment is infinite since involves the reception of pain over an infinite period of time). But if this punishment we will receive when we are judged by God (according to Jesus' parable) is temporary, then it's purgatory. Thus Jesus says, "You will not get out until you have paid the last penny," because there is a time when your finite punishment due to the finite, human dimension of your sins will be over.
In any event, more than enough has been said to show the inaccuracy of the charge that purgatory is an unbiblical doctrine. In reality, it is very firmly rooted in Scripture.
11. "No Protestant could believe it."
Sorry, but this is also false. There are Protestants who believe in purgatory. One who was very explicit about it was C.S. Lewis. In his Letters to Malcom, he wrote:
"Of course I pray for the dead. The action is so spontaneous, so all but inevitable, that only the most compulsive theological case against it would deter me. And I hardly know how the rest of my prayers would survive if those for the dead were forbidden. At our age, the majority of those we love best are dead. What sort of intercourse with God could I have if what I love best were unmentionable to him?"
"I believe in Purgatory. . . . Our souls demand Purgatory, don't they? Would it not beak the heart if God said to us, 'It is true, my son, that your breath smells and your rags drip with mud and slime, but we are charitable here and no one will upbraid you with these things, nor draw away from you. Enter into the joy'? Should we not reply, "With submission, sir, and if there is no objection, I'd rather be cleansed first.' "It may hurt, you know'--"Even so, sir.'"
"I assume that the process of purification will normally involve suffering. Partly from tradition; partly because most real good that has been done me in this life has involved it. But I don't think the suffering is the purpose of the purgation. I can well believe that people neither much worse nor much better than I will suffer less than I or more. . . . The treatment given will be the one required, whether it hurts little or much."
"My favorite image on this matter comes from the dentist's chair. I hope that when the tooth of life is drawn and I am 'coming round',' a voice will say, 'Rinse your mouth out with this.' This will be Purgatory. The rinsing may take longer than I can now imagine. The taste of this may be more fiery and astringent than my present sensibility could endure. But . . . it will [not] be disgusting and unhallowed."
But beyond Protestants like Lewis, who openly admit their belief in purgatory, it may be said that Protestants in general believe in purgatory, they just don't call it that. For every historic Protestant will admit that our sinning in this life does not continue into heaven. In fact, they will be quite insistent that although our sanctification is not complete in this life, it will be completed (instantaneously, they say) as soon as this life is over. But that is what purgatory is! -- the final sanctification, the purification. Thus it is permissible to say that many Protestants believe in purgatory without even realizing it.
A Positive Move
All of these reflections help one understand how to respond to challenges a Protestant may make to the doctrine of purgatory. However, since they are rebuttals, they do not of themselves constitute a positive explanation of the doctrine for Protestants. If one wants to do that -- to make an explanation of the doctrine rather than just to explain why the objections to it fail, then one should tie the preceding insights together and say something like this:
"Purgatory is the name that Catholics give to the final purification which occurs at the end of life. Because we still sin in this life, but will not be sinning when we are in glory, between death and glorification must come purification. This is something even Protestants admit. Purgatory is thus the final rush of our sanctification. It is our transition into glory. All through the Christian life God is purifying our hearts, giving us greater holiness, but this sanctifying process is not complete (or anything like complete) until the end of life. Thus what God did not choose to give us in this life, he chooses to give us once we are dead.
"The only additional points on which the Catholic Church insists concerning the final purification are that, like sanctification in this life, it can involve pain or discomfort, and that, as when someone is being sanctified in this life, we can pray for someone being sanctified in purgatory. The Church does not teach that purgatory occurs in a special region of the afterlife or even that it takes place over time, for we have little idea how time works in the afterlife, and purgatory may be instantaneous from our point of view."
You can then go on to back these up with the Bible verses and other material we have already discussed. In general, you should use the term "sanctification" rather than "purification" or "purging" because "sanctification" is a term Protestants understand and are comfortable with. By phrasing the doctrine in terms of sanctification it makes it intelligible to them and knocks down many of their key objections (for example, the idea that purgatory implies the sufferings of Christ were insufficient).
Thus it is helpful to talk about the souls being sanctified in purgatory and to describe purgatory as the final stage of sanctification. If you do this, it will make the conversation a lot smoother by talking in the language of the person you are talking with, rather than insisting he come over to using your language when he is only barely familiar (and highly skeptical, if not highly hostile) to the idea you are expressing.
Additionally, there are a couple of further points that you should make in your explanation, because many Protestants are confused about them.
Purgatory is not a middle destiny!
First, you should explain that purgatory is not a middle state between heaven and hell. This encourages the Protestant to think of it as not only a distinct region of the afterlife (something the Church does not teach) but, even worse, that purgatory is a middle destiny between heaven and hell. This it totally false, and you should emphasize quite strenuously to the Protestant that everyone who goes to purgatory goes to heaven. In fact, the reason one goes to purgatory is so that one can be fitted for life in heaven. Purgatory thus constitutes the cloakroom of heaven, the place you go to get spiffed up before being ushered into the Throne Room.
For this reason, you should totally avoid any language like, "Purgatory is where you go when you aren't bad enough for hell but not good enough for heaven." This language, besides sounding legalistic, is also going to get a Protestant thinking that purgatory is some kind of middle destiny rather than a temporary phenomenon. Instead, use the language the Church uses:
"All who die in God's grace and friendship, but still imperfectly purified, are indeed assured of their eternal salvation; but after death they undergo purification, so as to achieve the holiness necessary to enter the joy of heaven" (Catechism of the Catholic Church 1030).
Thus one should put the emphasis where it belongs, on the incomplete purification of the person rather than saying, "not good enough," which implies (at least to Protestant ears) a legalistic earning of heaven.
The Joys of Purgatory
To further break down the Protestant's barrier to comprehending the doctrine, point out that the Church in no way teaches that purgatory is all pain. In fact, some of the greatest saints and theologians have stressed that since the soul is in closer union with God than it is here on earth, one experiences correspondingly greater joys. Thus St. Catherine of Genoa wrote:
"God inspires the soul in Purgatory with so ardent a movement of devoted love that it would be sufficient to annihilate her were she not immortal. Illumined and inflamed by this pure charity, the more she loves God, the more she detests the least stain that displeases him, the least hindrance that prevents her union with him."
She also wrote:
"Apart from the happiness of the saints in heaven, I think there is no joy comparable to that of the souls in purgatory. An incessant communication with God renders their happiness daily more intense, and this union with God grows more and more intimate, according as the impediments to that union, which exist in the soul, are consumed. These obstacles . . . are the rust and the remains, as it were, of sin; and the fire continues to consume them, and thus the soul gradually expands under the divine influence. Thus, according as the rust diminishes and the soul is laid bare to the divine rays, happiness is augmented. The one grows and the other wanes until the time of trial is elapsed . . . With regard to the will of these souls, they can never say that these pains are pains, so great is their contentment with the ordinance of God, with which their wills are united in perfect charity."
In fact, the souls in purgatory have a large number of reasons for joy: (a) freedom from the committing of sin, (b) freedom from the desire to sin, (c) closer unity with God and Christ, (d) certainty of one's final salvation in a way not possible in this life, (e) a final and full appreciation of just how gracious God has been to one, (f) a final and full appreciation of just how much God loves one, (g) the at last unencumbered and pure love we will feel for God and for others, (h) partial rewards which may be given in anticipation of one's entrance into the full glory of heaven at the end of purgatory.
What's more, there is no teaching that the pains of purgatory outweigh the joys of purgatory. As St. Catherine says, "they can never say that these pains are pains, so great is their contentment with the ordinance of God, with which their will are united in perfect charity." It may (and in my view, it is quite likely) that the pain of seeing some of one's works go up in smoke is more than overbalanced by the joy of seeing some of them remain and inwardly hearing, "Well done, thou good and faithful servant," from the ever-loving and infinitely good Source of our redemption, our life, and our very existence.
Keep the doctrine in perspective
Finally, urge your Protestant brother or sister to keep the doctrine of purgatory in perspective. Protestants often feel (as I know because I was one) that Catholics place as much emphasis on given doctrines as Protestant anti-Catholic literature does. Thus, for example, when a Protestant thinks about a Catholic, he will more often think of him as someone which believes in purgatory rather than someone which believes in the Trinity, and he can mistakenly slip into thinking that purgatory is a more important doctrine to a Catholic than the Trinity.
Thus, because Protestant anti-Catholic polemics focus on areas of (real or perceived) disagreement with Catholics, these areas assume a greater prominence in the Protestant's mind and buys into a distorted view of how important given doctrines are to Catholics. Thus Protestants often imagine Catholicism is a religion of nothing but saints and statues and beads and works and penances and purgatory and suffering and a whole host of minor issues.
In doing this, they are straining at gnats but swallowing camels, missing "the weightier matters" of the Catholic faith and realizing what is more important to Catholics than not. Catholicism is in actuality a religion of God and Christ and the Trinity and redemption and forgiveness and faith and grace and joy, as illustrated by the fact that if you go to Mass and simply listen to the Church's official prayers, you hear a lot more about God and Christ and grace and joy than you do about saints and statues and beads and purgatory.
This should be pointed out, forcefully and repeatedly, to a Protestant brother so that he will have a better understanding of the essence of Catholic teaching and Catholic life, rather than assuming the discussion he hears in Protestant treatment is representative of the emphases Catholics themselves place on matters.
To this end, actually showing him the section on purgatory in the Catechism of the Catholic Church might be beneficial, since it is only three paragraphs out of seven hundred and fifty pages of explaining what the faith is about. To this end, let's close by simply looking at the Catechism's section on purgatory and let the Church speak for itself:
THE FINAL PURIFICATION, OR PURGATORY
1030 All who die in God's grace and friendship, but still imperfectly purified, are indeed assured of their eternal salvation; but after death they undergo purification, so as to achieve the holiness necessary to enter the joy of heaven.
1031 The Church gives the name Purgatory to this final purification of the elect, which is entirely different from the punishment of the damned.[Cf. Council of Florence (1439): DS 1304; Council of Trent (1563): DS 1820; (1547): 1580; see also Benedict XII, Benedictus Deus (1336): DS 1000] The Church formulated her doctrine of faith on Purgatory especially at the Councils of Florence and Trent. The tradition of the Church, by reference to certain texts of Scripture, speaks of a cleansing fire:[Cf. 1 Cor 3:15; 1 Pet 1:7]
"As for certain lesser faults, we must believe that, before the Final Judgment, there is a purifying fire. He who is truth says that whoever utters blasphemy against the Holy Spirit will be pardoned neither in this age nor in the age to come. From this sentence we understand that certain offenses can be forgiven in this age, but certain others in the age to come."[St. Gregory the Great, Dial. 4, 39: PL 77, 396; cf. Mt 12:31]
1032 This teaching is also based on the practice of prayer for the dead, already mentioned in Sacred Scripture: "Therefore [Judas Maccabeus] made atonement for the dead, that they might be delivered from their sin."[2 Macc 12:46] From the beginning the Church has honored the memory of the dead and offered prayers in suffrage for them, above all the Eucharistic sacrifice, so that, thus purified, they may attain the beatific vision of God.[Cf. Council of Lyons II (1274): DS 856] The Church also commends almsgiving, indulgences, and works of penance undertaken on behalf of the dead:
"Let us help and commemorate them. If Job's sons were purified by their father's sacrifice, why would we doubt that our offerings for the dead bring them some consolation? Let us not hesitate to help those who have died and to offer our prayers for them."[St. John Chrysostom, Hom. in 1 Cor. 41, 5: PG 61, 361; cf. Job 1:5]