St. Thomas Aquinas and St. Augustine both teach that the fire of Purgatory is the same fire that burns in hell.
Dr. Scott Hahn says that the fire of Purgatory is the consuming fire of God.
Therefore, Catholic scholars do not rule out that the fire of Purgatory is never extinguished.
I think that St. Thomas would have been more accurate if he said that the fire of purgatory is
similar to, rather than exactly the same as, the fire that burns in hell. The fire of purgatory serves two purposes: first, it provides temporary punishment to the elect for their small offenses; second, it cleanses and purifies their souls of all earthly attachments, so that they yearn more eagerly for God. The fire of hell, on the other hand, serves only to provide eternal punishment both for the demons who rebelled against God and the damned souls who, by their own choice, have separated themselves from Him.
To the extent that the purgatorial fire and the hell fire provide punishment, then they are the same. But in so far as the purgatorial fire cleanses the soul while the hell fire merely torments it, they are different. This is why the Catechism of the Catholic Church states: “The Church gives the name
Purgatory to this final purification of the elect,
which is entirely different from the punishment of the damned”(CCC # 1031 - boldface is my own addition for emphasis.)
The punishment provided by the fire of purgatory is similar to the punishment provided by hell fire in the sense that they both consist in not being able to see God face to face. Being deprived of the beatific vision causes in the soul the so-called “pain of loss.” However, even as a punishment the two fires are different, because hell fire is eternal while the purgatorial fire is only temporary.
For this reason, the souls in purgatory do not suffer the same way as the the souls in hell, although both are deprived of the vision of God. The souls in purgatory suffer because they are yearning for God. Their yet unsatisfied love for God is, for them, a consuming fire (to borrow the phrase from Dr. Hahn). They can’t wait to see Him, and His absence (even if temporary) is to them a source of great pain. However, their hearts are not angry but hopeful, knowing that they will eventually see Him whom their hearts desire.
On the other hand, the damned souls (in hell) are angry at God, desperate and bitter, because they know that they have lost a great Good with no hope of recovery. They are jealous, too, and full of hatred, not only for God but also for all His friends. Unlike the souls in purgatory, the damned souls are hopeless, and their sufferings do not cleanse them, but only serve to make their hearts immutably fixed in evil.
So, DeMaria, is purgatorial fire the same as hell fire? I think not.