The term “limbo” is used in three different ways:
1. limbo as a fringe or upper level of Hell
2. limbo as a fringe or upper level of Purgatory
3. limbo as a third final destination, that is not part of Hell, or Purgatory, or Heaven
1. Limbo as a fringe or upper level of Hell
The word “limbo” means “fringe”. The limbo of Hell is that part of Hell where the souls are punished the least of all. This concept, that the souls in Hell have different degrees and types of punishment, is a dogma taught infallibly by two Ecumenical Councils.
The Second Council of Lyons: “The souls of those who die in mortal sin or with original sin only, however, immediately descend to hell, yet to be punished with different punishments.”
The Council of Florence: “But the souls of those who depart this life in actual mortal sin, or in original sin alone, go down straightaway to hell to be punished, but with unequal pains.”
And this point is clear also from the teaching of Pope Innocent III: “The punishment of original sin is the deprivation of the vision of God, but the punishment of actual sin is the torments of everlasting hell….” [Denzinger, n. 410]
Persons who die with no mortal sins on their conscience other than “original sin alone” are sent to the part of Hell where the only punishment is “the deprivation of the vision of God.” But they are punished. And that particular punishment is the main punishment of Hell.
Catechism of the Catholic Church: “The chief punishment of hell is eternal separation from God, in whom alone man can possess the life and happiness for which he was created and for which he longs.” [CCC 1035]
The CCC teaches that human persons cannot have true happiness apart from God, and that all persons in Hell are eternally separated from God. Therefore, no one in Hell is happy, in any sense of the word, not even in the limbo of Hell. For the punishment of the limbo of Hell is “the deprivation of the vision of God.”
Therefore, it is a serious doctrinal error to claim that any souls in the limbo of Hell have “perfect natural happiness”. This incorrect idea is based on theological opinions by Saints, opinions formed prior to the above quoted magisterial teachings. Catholics today may not hold that unbaptized babies have perfect natural happiness in the limbo of Hell. That opinion is now clearly and thoroughly refuted by magisterial teaching. It is no longer a tenable or faithful opinion, as it once was.
In my theological opinion, all prenatals, infants, and young children, who die without formal baptism, receive a baptism of blood, which gives them the state of sanctifying grace, prior to death. Therefore, they go to Heaven, not to the limbo of Hell and not to any part of Hell. See my post: The Hope of Salvation for Infants Who Die Without Being Baptized.
Who, then, goes to the limbo of Hell? In my view, only adults who die guilty and unrepentant from the actual mortal sin of omission of never having found sanctifying grace, by one of the three forms of baptism (water, desire, blood), despite ample opportunity, go to the limbo of Hell. No prenatals, infants, or young children have had ample opportunity to obtain the state of grace, so they cannot be guilty of that sin of omission. Therefore, only adults can possibly go to the limbo of Hell, where they suffer least of all the souls in Hell, but they do suffer eternal punishment.
2. Limbo as a fringe or upper level of Purgatory
This version of limbo is called the limbo of the Fathers, as it is the place to which are sent the Old Testament fathers, and all other persons who died in the state of grace (by a baptism of blood or desire), prior to the establishment of the Sacrament of Baptism, and prior to the salvific death of Jesus Christ. They waited in the limbo of the Fathers, without any punishment or suffering, except the suffering of the as-yet-unfulfilled hope of Heaven. They may well have suffered in Purgatory proper, for any temporal punishment due for venial sins or for repented mortal sins. But after they completed their time in Purgatory, they waited for Christ in the limbo of the Fathers, which can be conceptualized as an upper level of Purgatory.
The most common theological opinion is that the limbo of the Fathers no longer exists, as it was no longer needed once Christ died for our salvation. However, my opinion is that this limbo still exists, as an upper level of Purgatory, and is used for prenatals, infants, and young children who die without formal baptism, but in the state of grace due to a baptism of blood. They do not go directly to Heaven, since they require or at least benefit from time in the limbo of Purgatory, where they receive the development that their souls were denied on earth, due to their very short lifespans, and where they learn about Christ explicitly before entering Heaven. But this particular point is a speculative theological opinion.
3. Limbo as a third final destination, that is not part of Hell, or Purgatory, or Heaven
Most people use the term limbo in the third way, meaning a place where the soul dwells eternally, a place which is not part of Heaven or Hell or Purgatory. Given the recent teachings of the Magisterium on salvation, including in Vatican II, the CCC, and Redemptoris Missio, this version of limbo is no longer theologically tenable. In my book Forgiveness and Salvation for Everyone, I argue that the teachings of the Magisterium are now sufficient to imply that all prenatals, infants, and young children go to Heaven (perhaps by way of the limbo of Purgatory), and none of them are sent to the limbo of Hell, nor to limbo as a third final destination.
The Church now teaches that human persons cannot be truly happy apart from God. But in this version of limbo, the souls are separated from God and also lack the state of sanctifying grace. So it is not possible for them to have even the proposed limited natural happiness of limbo.
The existence of the limbo of Hell is dogma. The limbo of Hell is a place of eternal punishment, where the souls are punished less than other souls in Hell. No prenatals, infants, and young children go there, and no one there is happy, in any sense of the word.
The existence of the limbo of the fathers is a teaching of the Church. Whether or not this version of limbo still exists is an open theological question. I contend that it does still exist. However, it is a temporary place, not an eternal final destination.
The existence of limbo as a third final destination can be absolutely excluded, based on recent magisterial teachings.
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