Purgatory is a supernatural reality that exceeds our reason. We know about it because God has revealed it to us, but it remains very mysterious. We will only understand what Purgatory really is after we die.
Nevertheless, the Church asks us to look upon this mystery with the eye of faith and understanding.
St Paul speaks of our all-too-human, sometimes even childish, conception of the things of God: “When I was a child, I spoke as a child, I understood as a child, I thought as a child. But when I became a man, I put away the things of a child.” He further goes on to explain that while on this side of the grave, we only see things as “through a glass, in a dark manner,” but that will give way to vision, in the “face to face” that the soul will come to enjoy in the presence of God.
As with all supernatural mysteries, the only way we may know what it really is, is to listen to what God says: through the teaching of the Magisterium.
It is de fide that Purgatory exists. Although it was only formally defined by the Church in the second Council of Lyons (1274), the belief in the existence of Purgatory has always been held by the Church, as evidenced by the teaching of the Church Fathers and even the inscriptions found in the catacombs dating back to the 2nd century.
During the first four centuries of the Christian era, the existence of purgatory was commonly taught in the Church, as seen in its universal practice of offering prayers and sacrifices for the dead. St Augustine, preaching in the 5th century, cites the ancient liturgies and the custom of prayers for the dead as proof of the existence of Purgatory.
Protestantism and its wholesale denial of the propitiatory nature of the Mass destroyed belief in the necessity of succouring the holy souls. As a result, the Council of Trent explicitly declares
that there is a Purgatory, and that the souls there detained are relieved by the suffrages of the faithful, but chiefly by the acceptable sacrifice of the altar
Canon XXX of Session 6 condemns those who deny this dogma:
If any one saith, that, after the grace of Justification has been received, to every penitent sinner the guilt is remitted, and the debt of eternal punishment is blotted out in such wise, that there remains not any debt of temporal punishment to be discharged either in this world, or in the next in Purgatory, before the entrance to the kingdom of heaven can be opened (to him); let him be anathema.
Unfortunately, the new liturgy and the idea of universal salvation proposed by the modernists has obscured the reality of Purgatory. But the God’s mercy and justice demands that a place of expiation after death exists; the faith of the Church in Purgatory is based on punishment due to sin that remains to be purged from the soul after death. To deny that Purgatory exists is both heretical and erroneous. As St Thomas states,
The justice of God requires that sin be put in order by the punishment that is owed for it; if then, someone dies with contrition for his sin and being absolved of it, but before having made the satisfaction owed, it is necessary that after this life he be punished. And thus those who deny purgatory speak against divine justice.
Purgatory is an instrument of God’s mercy: only the flames of divine love can remove the stains that still remain on the soul after death. The soul, explains St Catherine of Genoa in her Treatise on Purgatory, voluntarily throws herself into these flames because it recognises that the un-expiated faults that mar the beauty of its soul make it impossible to approach God, Who is Purity. She continues,
If the soul could find a more painful Purgatory in which it could be purified more quickly, it would plunge itself in it immediately, constrained by the reciprocal burning love between it and God.
These souls are thus in complete union with the will of God. They have perfect charity, in that they no longer have any culpability before God, because they are only suffering from punishment, and not from the fault, like the damned in hell. They hate sin, and regret to have offended divine goodness.
But how can we apply this doctrine of Purgatory to our own lives? These souls who are detained there are, to a certain extent, a model and image of our own lives, especially for Religious. For we are live as dead to the world, and give ourselves completely to God forever, just like them. Now is the acceptable time, as St Paul says, to do penance and purify ourselves so that at the moment of our death, our divine Bridegroom may indeed say, “Come, ye blessed of my Father, possess you the kingdom prepared for you from the foundation of the world” (Matt 25:34).