Pope St. Innocent, 414: “But that which Your Fraternity asserts the Pelagians preach, that even without the grace of Baptism infants are able to be endowed with the rewards of eternal life, is quite idiotic.” (Jurgens, The Faith of the Early Fathers, Vol. 3: 2016.)
St. Augustine, Letter to Jerome, 415: “Anyone who would say that even infants who pass from this life without participation in the Sacrament [of Baptism] shall be made alive in Christ truly goes counter to the preaching of the Apostle and condemns the whole Church, where there is great haste in baptizing infants because it is believed without doubt that there is no other way at all in which they can be made alive in Christ.” (Faith of the Early Fathers, Vol. 3:1439)
Pope Eugene IV, Council of Florence, “Letentur coeli,” Sess. 6, July 6, 1439, ex cathedra: “We define also that… the souls of those who depart this life in actual mortal sin, or in original sin alone, go straightaway to hell, but to undergo punishments of different kinds.” (Denz. 693)
Pope Pius VI, Auctorem fidei, Aug. 28, 1794:
“26. The doctrine which rejects as a Pelagian fable, that place of the lower regions (which the faithful generally designate by the name of the limbo of the children) in which the souls of those departing with the sole guilt of original sin are punished with the punishment of the condemned, exclusive of the punishment of fire, just as if, by this very fact, that these who remove the punishment of fire introduced that middle place and state free of guilt and of punishment between the kingdom of God and eternal damnation, such as that about which the Pelagians idly talk” – **Condemned **as false, rash, injurious to Catholic schools. (1954 Denz. 1596).
Pope Pius VI condemns the idea of some theologians that infants who die in original sin suffer the fires of Hell. At the same time, he confirms that these infants do go to a part of the lower regions (i.e., Hell) called the limbo of the children. They do not go to Heaven, but to a place in Hell where there is no fire.
Pope Eugene IV, Council of Florence, Session 11, Feb. 4, 1442, ex cathedra: “Regarding children, indeed, because of danger of death, which can often take place, when no help can be brought to them by another remedy than through the sacrament of baptism, through which they are snatched from the domination of the Devil [original sin] and adopted among the sons of God, it advises that holy baptism ought not be deferred for forty or eighty days, or any time according to the observance of certain people…” (Denz. 712)
Eugene IV here defines infallibly that there is no other remedy for infants to be snatched away from the dominion of the devil (i.e., original sin) other than the Sacrament of Baptism. This means that anyone who obstinately teaches that infants can be saved without receiving the Sacrament of Baptism is a heretic, for he is teaching that there is another remedy for original sin in children other than the Sacrament of Baptism.
Pope Martin V, Council of Constance, Session 15, July 6, 1415 - Condemning the articles of John Wyclif - Proposition 6*: “*Those who claim that the children of the faithful dying without sacramental baptism will not be saved, are stupid and presumptuous in saying this.”- Condemned (Decrees of the Ecumenical Councils, Vol. 1, p. 422.)
The arch-heretic John Wyclif was anathematized for this assertion.
Pope Paul III, The Council of Trent, On Original Sin, Session V, ex cathedra: “If anyone says that recently born babies should not be baptized even if they have been born to baptized parents; or says that they are indeed baptized for the remission of sins, but incur no trace of the original sin of Adam needing to be cleansed by the laver of rebirth for them to obtain eternal life, with the necessary consequence that in their case there is being understood a form of baptism for the remission of sins which is not true, but false: **let him be anathema.” **(Denz. 791).
This means that anyone who asserts that infants don’t need the “laver of rebirth” (water baptism) to attain eternal life is teaching heresy.
No. Limbo isn’t going anywhere. The best that will be done on any non-pronouncment pronouncement is that it will be politically suppressed and theologically obfuscated.