The word purgatory means "a place of purification," reflecting the Catholic teaching on what happens to many souls before they reach Heaven.
The concept of Purgatory can be a strange one for many to accept, as it can seem like a middle place, between Heaven and Hell.
Yet, in reality, Purgatory is much more related to Heaven, and its name helps explain what happens in this stage of the afterlife.
The English word purgatory comes from the Latin purgare, “to make clean, to purify.“
It is a place of final purification before a soul reaches the gates of Heaven.
The Catechism of the Catholic Church expands on this idea.
The Church gives the name Purgatory to this final purification of the elect, which is entirely different from the punishment of the damned. 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: 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.CCC 1031
C.S. Lewis (although he was not a Catholic) gave a profound (and comical) description of Purgatory that connects to this definition. He wrote in The Great Divorce:
“Our souls demand Purgatory, don’t they? Would it not break 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 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.”
It could be described as a washroom before reaching the Wedding Feast of the Lamb.
Not all souls require this final purification, but many will, and it is seen as a part of God’s Divine Mercy that it exists, to give our souls the chance to reach Heaven.