A - Thanks for the questions! As we always do, we need to define some terms. Jaroslav Pelikan defines doctrine as "what the Church believes, teaches, and confesses on the authority of the Word of God." The "Word of God" is a person, not just a thing. Word of God = Jesus. He is the fullness of God the Father's revelation to us. This revelation is handed on in two forms that make the whole of the Word of God = Sacred Scripture + Sacred Tradition. Thus, doctrine has to have an apostolic dimension to it (from Jesus and the Apostles) . Does it have to be explicit in Sacred Scripture? No. From this we can see that:
- "believes" is seen implicit in the way we worship, live and pray as a Church.
- "teaches" is explicit and in day-to-day teachings of the Church.
- "confesses" is about solemn confessions of faith in times of crisis. Found in Creeds and dogmas.
Limbo, as understood here, is speaking about the place where unbaptized babies (or children who haven't reached the age where they can personally sin) go after they die. Some theologians (e.g., St. Thomas Aquinas) have hypothesized this is the most we can hope for.
There is another limbo that isn't being addressed, which is commonly called the Limbo of the Fathers. This is where the Old Testament patriarchs, prophets, and righteous people would have been before Christ came to open the gates of heaven. This was not part of the discussion of the Vatican.
So, the questions we have to answer:
1 - Was Limbo Doctrine?
2 - Is this still an acceptable theory?
1 - No. It was never part of what the Church believes, teaches and confesses on the authority of The Word of God. It is theological conjecture. While certain Popes/Bishops/Theologians have furthered this teaching, it isn't part of the deposit of faith. Limbo is not a dogma or doctrine of the Church and never has been.
2 - Is it still an acceptable theory? Yes, but it is not a preferred theory. This is because the Church does not believe it adequately answers the question of what happens to babies who are unbaptized. In fact, we just don't know what happens, but we hope for the best. We cannot say with certainty what happens to those souls.
Here is what the document, The Hope of Salvation for Infants Who Die Before Baptism, said, after saying limbo is not doctrine, but theological conjecture that can be considered still valid:
The conclusion of this study is that there are theological and liturgical reasons to hope that infants who die without baptism may be saved and brought into eternal happiness, even if there is not an explicit teaching on this question found in Revelation. However, none of the considerations proposed in this text to motivate a new approach to the question may be used to negate the necessity of baptism, nor to delay the conferral of the sacrament. Rather, there are reasons to hope that God will save these infants precisely because it was not possible to do for them that what would have been most desirable— to baptize them in the faith of the Church and incorporate them visibly into the Body of Christ.Another reason for this document is because of all of the aborted babies we have in our world today. This is a better and more theologically precise answer. Guessing at limbo doesn't help a mother who is seeking an answer and healing (after repenting). That being said, a Catholic can still hold that Limbo is true as long as they prayerfully consider this most recent teaching of the Church.
There is no back-tracking here or change in doctrine. Not everything the Church explores as a theological possibility is doctrine, even if a Pope or Bishop write about it. There are levels of teaching in the Catholic Church that unfortunately get jumbled together by many. I often see the error of saying that anything the Pope says is infallible. This is just a failure to understand the levels of Church teaching.
Suffice it to say that it is a common error by both Catholics and non-catholics as seen in how the mass media has portrayed this exploration as a "change in Catholic doctrine".
I hope this helps.