Since the Church did not receive any divine revelation on the nature of Purgatory, and since the Church declined to make any official statements on its nature, it is only natural that people of different eras are going to come to different views of what precisely constitutes the Purgatorial experience.(Source: Sungenis' article oddly titled: James White, Alive but Still Struggling)
... we have not settled on the nature of Purgatory ...
... the nature of Purgatory is an admitted area of unsettled knowledge in the Catholic Church ...
After we have already admitted that being in the 15% area of unsettled doctrine
the nature of Purgatory continues to be debated among “modern Roman Catholic advocates,” the truth is, it really doesn’t matter a whole lot. The fact is, Purgatory exists. It can be shown from Scripture, the Patristics, the medievals, and the Magisterium. Whether it is “days” or some other measurement is not really a make-or-break issue.
The underlying problem here, though, is that Sungenis has not fully identified the reason for the lack of common assent regarding the nature of Purgatory. While it is true that God has not revealed the nature of "Purgatory," the primary reason for the lack of common assent regarding the nature of Purgatory is that (a) Purgatory is a fiction and (b) Purgatory is a relatively new fiction. The medieval era in the West is where we really see the development of a view of Purgatory. There is no mention of any "Purgatory" in the fathers.
As Jacques Le Goff explains, "Until the end of the twelfth century the noun purgatorium did not exist: the Purgatory had not yet been born." (Jacques Le Goff, The Birth of Purgatory, p. 3 - see also, Appendix II: "Purgatorium," the History of a Word)(emphasize is Le Goff's) There may well have been vague concepts of purgation either upon death or at the day of judgment (or the like) but the idea of a third state or place given the name "Purgatory" was a long time in development from some vague comments about purging by Augustine in the 5th century (I'll leave the debate over those comments for another post).
But there is an interesting background against which Sungenis is making his claim. Benedict XV praised Dante Alighieri's work (The Divine Comedy: Inferno, Purgatorio, Paradisio) this way:
It is thus that, according to the Divine Revelation, in this poem shines out the majesty of God One and Three, the Redemption of the human race operated by the Word of God made Man, the supreme loving-kindness and charity of Mary, Virgin and Mother, Queen of Heaven, and lastly the glory on high of Angels, Saints and men; then the terrible contrast to this, the pains of the impious in Hell; then the middle world, so to speak, between Heaven and Hell, Purgatory, the Ladder of souls destined after expiation to supreme beatitude. It is indeed marvellous how he was able to weave into all three poems these three dogmas with truly wrought design.- Benedict XV, In Praeclara Summorum, Section 4, 30 April 1921
Dante Alighieri lived from about 1265 to 1321. His work on the subject of the afterlife, including Purgatory, is one whose influence in the late medieval period, particularly in Italy, is hard to overstate. He is referred to both as the Supreme Poet of Italy and the Father of the Italian language.
His work makes clear that his view of Purgatory is that it is a place like Heaven or Hell in that it is a place having space and time. It is, for Dante, a Mountain that is to be climbed. We also see a similar view of Purgatory as a definite place in the works of Thomas Aquinas:
Article 2. Whether it is the same place where souls are cleansed, and the damned punished?- Thomas Aquinas (as completed by Reginald of Piperno), Summa Theologica, Supplement to the Third Part, Appendix 2, Article 2 (Although Reginald is given credit for adding this material to the Summa Theologica, the material is essentially taken word for word from Thomas Aquinas' Commentary on [Peter Lombard's] Sentences, Book IV, Distinction 21, Article 1, with some omissions of the materials found there, but no obvious insertions that affect the meaning)
Objection 1. It would seem that it is not the same place where souls are cleansed and the damned punished. For the punishment of the damned is eternal, according to Matthew 25:46, "These shall go into everlasting punishment [Vulgate: 'fire']." But the fire of Purgatory is temporary, as the Master says (Sent. iv, D, 21). Therefore the former and the latter are not punished together in the same place: and consequently these places must needs be distinct.
Objection 2. The punishment of hell is called by various names, as in Psalm 10:7, "Fire and brimstone, and storms of winds," etc., whereas the punishment of Purgatory is called by one name only, namely fire. Therefore they are not punished with the same fire and in the same place.
Objection 3. Further, Hugh of St. Victor says (De Sacram. ii, 16): "It is probable that they are punished in the very places where they sinned." And Gregory relates (Dial. iv, 40) that Germanus, Bishop of Capua, found Paschasius being cleansed in the baths. Therefore they are not cleansed in the same place as hell, but in this world.
On the contrary, Gregory says [The quotation is from St. Augustine (De Civ. Dei i, 8)]: "Even as in the same fire gold glistens and straw smokes, so in the same fire the sinner burns and the elect is cleansed." Therefore the fire of Purgatory is the same as the fire of hell: and hence they are in the same place.
Further, the holy fathers; before the coming of Christ, were in a more worthy place than that wherein souls are now cleansed after death, since there was no pain of sense there. Yet that place was joined to hell, or the same as hell: otherwise Christ when descending into Limbo would not be said to have descended into hell. Therefore Purgatory is either close to, or the same place as, hell.
I answer that, Nothing is clearly stated in Scripture about the situation of Purgatory, nor is it possible to offer convincing arguments on this question. It is probable, however, and more in keeping with the statements of holy men and the revelations made to many, that there is a twofold place of Purgatory. One, according to the common law; and thus the place of Purgatory is situated below and in proximity to hell, so that it is the same fire which torments the damned in hell and cleanses the just in Purgatory; although the damned being lower in merit, are to be consigned to a lower place. Another place of Purgatory is according to dispensation: and thus sometimes, as we read, some are punished in various places, either that the living may learn, or that the dead may be succored, seeing that their punishment being made known to the living may be mitigated through the prayers of the Church.
Some say, however, that according to the common law the place of Purgatory is where man sins. This does not seem probable, since a man may be punished at the same time for sins committed in various places. And others say that according to the common law they are punished above us, because they are between us and God, as regards their state. But this is of no account, for they are not punished for being above us, but for that which is lowest in them, namely sin.
Reply to Objection 1. The fire of Purgatory is eternal in its substance, but temporary in its cleansing effect.
Reply to Objection 2. The punishment of hell is for the purpose of affliction, wherefore it is called by the names of things that are wont to afflict us here. But the chief purpose of the punishment of Purgatory is to cleanse us from the remains of sin; and consequently the pain of fire only is ascribed to Purgatory, because fire cleanses and consumes.
Reply to Objection 3. This argument considers the point of special dispensation and not that of the common law.
Notice that in this discussion, Thomas Aquinas (lived about 1225 - 1274) suggests that Purgatory occupies two places: one place is in or below Hell - the other is at various specific times in other places for particular purposes.
Notice as well that Thomas Aquinas concedes that Scripture does not tell us about the "situation" (that is, the place where it is sited - it's location) of Purgatory. Thus, he's not willing to be dogmatic about it. However, Thomas Aquinas does believe that there were "revelations made to many" about Purgatory.
The bottom line is that, as Le Goff said, the Purgatory is something born in the 12th century. It is something that took shape as a definite place in the writings of folks like Dante and Thomas Aquinas in the 13th century. Yet it is something that one today hears promoted as simply a state, not a place, from sources like EWTN (example) based on comments such as the following from John Paul II:
Purification must be complete, and indeed this is precisely what is meant by the Church's teaching on purgatory. The term does not indicate a place, but a condition of existence.- John Paul II, General Audience, 4 August 1999, Section 5
So, while we certainly agree with Mr. Sungenis that Rome has not received divine revelation about the nature of Purgatory, we would simply take that a step further and note that the current teachings one gets from Rome (whether from the pope or anyone else) lack the authority of divine revelation generally. Scripture does not speak of a Purgatory, and there is no good reason for accepting the changing traditions of Rome on this subject. Waving ones hands and saying that the things that are not known are not important doesn't really address the issue behind the fact that Roman Catholics cannot even tell us with certainty whether Thomas Aquinas or John Paul II is right, when it comes to Purgatory.
N.B. As an aside, Mr. Sungenis makes reference to the idea that there is a "15% area of unsettled doctrine" in his religion. He made this number up out of thin air. He has no way of knowing how much additional doctrine his church will define this century or the next, and consequently he has no way of knowing whether the real number is 15% or 0.000001%. All he can really say is that his church makes more dogmatic statements than most other churches do.