When a human person dies, he or she is immediately judged by God. Everyone who dies unrepentant from one or more actual mortal sins is sent to Hell to be punished forever. Everyone who dies in a state of grace, having avoided all actual mortal sin or at least having repented and been forgiven by God, will have eternal life in Heaven. However, many persons first must undergo a purification in Purgatory, prior to entering Heaven. So there are two final destinations, Heaven and Hell.
Limbo means “fringe”. The limbo of the Fathers is a place where persons, who lived prior to Christ and who died in a state of grace, after their purification in Purgatory if needed, waited for Christ to open the gates of Heaven by His salvific death. I would describe the limbo of the Fathers as a fringe or upper level of Purgatory. There is no punishment or suffering there, except the suffering of the as yet unfulfilled hope of eternal life with God. The limbo of the Fathers is not a final destination; all who entered the limbo of the Fathers next entered Heaven.
A second place is also called limbo: the limbo of Hell. This place can be described as a fringe or upper level of Hell, where those souls go who died with the least culpability that still merits eternal punishment. The souls in the limbo of Hell have the chief punishment of Hell, the deprivation of the Beatific Vision of God (and all the consequent joys of Heaven). But they do not have the active punishments found in the lower regions of Hell, where souls go who sinned much more gravely.
The existence of the limbo of the Fathers is a teaching of the Church, perhaps falling under the infallibility of the ordinary and universal Magisterium. The limbo of Hell is also an infallible teaching of the Church, implied by the infallible teachings of two Ecumenical Councils.
A third proposed place is limbo as a third final destination, which is neither Heaven, nor Hell. This place is described as a place of perfect natural happiness, but without the Beatific Vision of God and all the consequent joys of Heaven. The existence of this place is not a dogma of the Church and is not currently taught by the Magisterium. It was proposed as a theological speculation, and perhaps taught, at one time, by the non-infallible Magisterium. I would characterize this idea as untenable.
There can be no limbo or fringe of Heaven, since Pope Benedict XII (the 12th, not the 16th) infallibly taught that everyone in Heaven has the Beatific Vision of God [Benedictus Deus].
The limbo of Hell is sometimes called the limbo of infants — referring to infants who die without formal baptism. However, the Magisterium has never taught that unbaptized prenatals, infants, and young children go there. It is assumed that these unbaptized little souls go to the limbo of Hell, because they supposedly die in a state of “original sin only” (or “orginal sin alone”), that is to say, with the guilt of original sin, but without the guilt of any actual mortal sin.
Now we come to the title subject of this article. Do the souls in the limbo of Hell have perfect natural happiness? Saint Thomas Aquinas held this to be true. But he lived over 700 years ago. After 700 years of magisterial teaching, some positions of Aquinas are not tenable today. After the time of Aquinas, two Ecumenical Councils (Lyons II, Florence) infallibly taught that the souls who die in a state of original sin alone go to Hell to be punished.
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.” [Denzinger 464]
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.” [Sixth Session]
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 410]
As we can see from the teaching of Pope Innocent and two Ecumenical Councils, if a person dies in a state of original sin alone, they receive punishment in Hell, though only the punishment of the deprivation of the Beatific Vision (and all that is consequent). Therefore, limbo as a third final destination is not tenable. Who would go to limbo as a third final destination? Only souls who die in a state of original sin alone. But the Magisterium teaches that such souls go to Hell.
The teaching on unequal or different punishment for souls in the limbo of Hell means that they are punished less, having only the culpability of original sin, and not various types of actual mortal sin, as the Councils taught. However, their punishment of deprivation is the chief punishment of Hell. So the souls in the limbo of Hell would therefore have that chief punishment, and would lack sanctifying grace as well as the infused virtues of love, faith, and hope. Therefore, they cannot have perfect natural happiness. They are not united to God in love, which requires the state of sanctifying grace. They do not have faith and hope. Indeed, they cannot hope for eternal life, since they are forever in Hell. They are not united to God by the Beatific Vision. They lack the company of the holy angels and holy souls in Heaven. They cannot be happy there. Human persons cannot have any type of true happiness apart from God and sanctifying grace.
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]
Pope Benedict XVI: “Human beings cannot completely fulfill themselves, they cannot be truly happy without God.” [Homily, Sunday, 24 May 2009]
Pope John Paul II: “Without God, man cannot fully find himself, nor can he find his true happiness.” [Homily, 9 November 1999]
So, at this point in time, the faithful cannot hold that the souls in the limbo of Hell have perfect natural happiness. They have the chief punishment of Hell, and they lack sanctifying grace and the infused virtue of love. Nor can we hold that limbo, as a third final destination that is neither Heaven, nor Hell, exists at all, for two Ecumenical Councils taught that the souls who die in original sin alone go to Hell, not to some third final destination.
At this point in time, is it a heresy to claim that the limbo of Hell is a place of perfect natural happiness? Yes, I would say it is a heresy. For that claim directly contradicts the teaching of two Ecumenical Councils that the souls in the limbo of Hell are punished with what the Catechism of the Catholic Church says is the chief punishment of Hell, while both Sacred Tradition and Sacred Scripture have always taught that Hell is a place of eternal punishments. It is contradictory to that teaching to say that some souls in Hell have perfect natural happiness. Tradition and Scripture have never taught that any type of happiness is possible in Hell.
Saint Thomas did not commit heresy in his writings, since, at the time, the Church had not yet taught the above quoted points on salvation and on Hell. But given the subsequent teachings of two Ecumenical Councils and the teachings of the CCC and the recent holy Pontiffs, it is no longer a tenable or faithful position to say that the limbo of Hell is a place of perfect natural happiness.
Must we hold, then, that unbaptized prenatals, infants, and young children are punished in the limbo of Hell? No, the Magisterium has not taught that prenatals, infants, and young children go there. I believe that these little children receive a baptism of blood, so that they die without the guilt of original sin, and in a state of grace, and therefore will have eternal happiness in Heaven forever.
Who goes to the limbo of Hell? Only those souls who die unrepentant from the actual mortal sin of omission of never having found sanctifying grace in this life, by any of the three forms of baptism, despite ample opportunity. They are culpability for being in the state of original sin alone, since they had ample opportunity to vanquish original sin by some form of baptism. Therefore, the limbo of Hell would contain only adults and perhaps some teenagers, but no little children. For little children lack sufficient opportunity to obtain the state of grace, and so are not culpable, to the extent of actual mortal sin, for that type of omission.
For more on this topic, see my book of salvation theology:
Forgiveness and Salvation for Everyone
Please take a look at this list of my books and booklets, and see if any topic interests you.