"Bertha said something such as the souls in purgatory are awaiting judgment. I told her that any soul in purgatory is on its way to Heaven. Hildy asked, "What about Limbo?" ...Can you make your next theology topic Limbo/purgatory?"
* -- I have changed the names of the parties involved to protect their identities, and to allow me to use some amusing names in their place.
So, a few questions are involved here:
1) Are the souls in purgatory awaiting judgment?
2) What's the deal with Limbo?
Let's do this!
As to the first question: are the souls in purgatory awaiting judgment?
Answer: negative. A soul in Purgatory has already been judged and is, as the reader correctly said, "on its way to Heaven." What's the deal with purgatory, then? If they aren't waiting to be judged, what are they doing there? The key to understanding Purgatory is right in its name: Purg-atory, as in purgation, purging.
Every human being ends his life either in the state of friendship with God or not in friendship with God. For those who are in friendship with God, for those who fundamentally desire God and whose actions in their lives have reflected that and oriented them toward God, they will get what they want: spending eternity in the blessed presence of the Holy Trinity, beholding their glory (the Beatific Vision).
BUT we must remember that Scripture of heaven says "nothing impure will enter" (Revelation 21:27). Now, though we may die in the friendship of God, we may still have on our souls venial sins or attachment to sin that make us impure. So, before we can enter heaven, this impurity needs to be purged from our souls, via the prayers of the living and the merits of Christ and the saints. (This is why it's so important to pray for the dead! We help them get to heaven!) This state of purgation we call Purgatory.
Think of Purgatory as the "wash room" or "mud room" in your home, where you clean off whatever dirt or grime you picked up outside before coming in to the house.
As to the second question: what's the deal with Limbo?
Answer: Limbo was a solution posed by theologians to a problem they perceived. Follow me: Baptism removes original sin and puts us into friendship with God through Christ. Those who still have original sin on their souls are not in the friendship of God cannot enter Heaven, and are thus bound for Hell. But, the question arose, what about babies who die before they can be baptized? They still have original sin on their souls, but they never had the chance to get it removed, nor did they grow old enough to develop the capacity to choose or reject God by their actions. Does it seem right that these babies suffer Hell for all eternity?
That didn't sit right with people. Such a fate for babies with no personal fault seemed unthinkable with an all-merciful God involved. So, they proposed a solution: a state in which the unbaptized babies would not enjoy the Beatific Vision in Heaven, but neither would they suffer the pains of Hell. (They might suffer the pain of the loss of Heaven, but this would be minor.) This state came to be referred to as Limbo, and for many centuries was taught in the Church as a likelihood.
In recent years, though, the Church has deemed the theory unnecessary. As Catechism paragraph 1261 states:
As regards children who have died without Baptism, the Church can only entrust them to the mercy of God, as she does in her funeral rites for them. Indeed, the great mercy of God who desires that all men should be saved, and Jesus' tenderness toward children which caused him to say: "Let the children come to me, do not hinder them," allow us to hope that there is a way of salvation for children who have died without Baptism. All the more urgent is the Church's call not to prevent little children coming to Christ through the gift of holy Baptism.This is to say, "We can't say for certain what happens, but we can trust in the mercy of God." But if God has revealed that Baptism is necessary for salvation, how can this be? Catechism paragraph 1257 gives a quotation that gives us the principle by which we may have this hope: "God has bound salvation to the sacrament of Baptism, but he himself is not bound by his sacraments." That is: God has bound us to receive the sacraments, but He, being their Author, is free and able to act outside of them if He chooses. This allows for the possibility of salvation of those who lived before Christ; or those who lived after but never had the opportunity to be baptized, like an inhabitant of 9th-century Papua New Guinea who never heard the Gospel message; or those who perhaps have only ever been given a distorted view of Christ and His Church and reject that distortion and thus are not truly rejecting God or refusing baptism. We deem it fitting of God, our merciful Father, to extend his grace in such a way in the case of unbaptized babies.
Some may hear such an idea and think, "Post-Vatican II claptrap!" I would give two responses to that: 1) I've seen this phrase used at least as far back as Peter Lombard, the 12th-century bishop of Paris and theologian whose Book of Sentences was THE textbook in the medieval Church; and I think it's older, but I can't find an earlier reference. The point is, it's an old and well-received idea. 2) Even the venerable Ludwig Ott in his Fundamentals of Catholic Dogma, written in the 1950s (before Vatican II) calls Limbo a theological assumption (p. 114), and theological assumptions are subject to revision.
So, neither Purgatory nor Limbo are places where souls are awaiting judgment; indeed, the Church does not even really teach Limbo as a theory anymore.
Hope that helps! Do ask follow-ups!