The Catechism says we may have some 'hope', but it doesn't overrule the Church's authoritative past teaching
In his response to me on limbo, Nicholas Senz asserts that we have “sufficient reason to believe that children who die without Baptism can be saved”. On the contrary, the 1980 CDF instruction Pastoralis Actio – which the Catechism cites on this point – plainly teaches: “The Church has thus shown by her teaching and practice that she knows no other way apart from Baptism for ensuring children’s entry into eternal happiness.”
Now, we may have particular reasons for hoping that some sub-group of infants who die without baptism might be saved. But it is straightforwardly inadmissible to claim that no one is punished for original sin only. For, towering above the low-level and even non-magisterial remarks that speak of possible exceptions to the necessity of water baptism in infants, stand two solemn definitions of the ecumenical council of Florence.
The council solemnly defines that those who die in original sin only go immediately to hell (of which limbo is technically a part, although it is a place of natural happiness beyond anything in this life) and that the sacrament of baptism is the only available remedy for original sin in infants. Ludwig Ott (whom Senz quotes) expresses the point like this: “Souls who depart this life in the state of original sin are excluded from the Beatific Vision of God”. Senz asks: “Does this teaching necessarily apply to the case of an infant or unborn child who dies without baptism?” But since an infant or unborn child is the only category of human being who can die in original sin only, it quite patently applies to them.
Senz claims Ott calls limbo an “assumption”, but this is misleading. What Ott calls an “assumption” is the belief that the punishment of such persons is the ‘special place’ of the least possible punishment. The belief that those who die in original sin only are excluded from beatitude Ott describes as a dogma.
The Catechism says we may “hope that there is a way of salvation for children who have died without baptism.” The easiest way to interpret this is with Cardinal Cajetan’s theory – that there may be a vicarious baptism of desire for the children of Christian parents who seek to but are unable (rather than unwilling) to get their child baptised. But for one thing, this is as the Catechism says a mere “hope”, a tolerated opinion; for another, it would not apply to the vast number of children who do not have Christian parents.
If one defines limbo as the state of those who die in original sin only, then its existence is a dogma. That does not certainly rule out Cardinal Cajetan’s “vicarious baptism” for some infants, and it does not answer every question about the details of limbo. But it does rule out Senz’s “sufficient reason”. As even the ITC confessed: “We emphasise that these are reasons for prayerful hope, rather than grounds for sure knowledge. There is much that simply has not been revealed to us”. But what has indeed been revealed to us is that “Souls who depart this life in the state of original sin are excluded from the Beatific Vision of God”, and it is in this bare exclusion that limbo consists.