Father Thomas Crean, O.P., has authored a brief and excellent article for Catholic Answers called Wrestling with the Fate of the Unbaptized. (Update [May 11, 2023]: The article is now published on Catholicism.org with the kind permission of the author and his Prior.) It is a robust defense of the dogmatic nature of the Limbus Infantium — the Limbo of Infants.
The Dominican theologian focuses on the binding dogmatic character of the teaching of the Council of Florence — in a passage we have referenced in at least one piece on this site: Limbo and the Mystical Body: on the Borderlands of Dogma.
Father Crean also turns to the subject of the non-authoritative ITC document on Limbo, which many falsely claimed “abolished limbo”:
In 2007, during the pontificate of Benedict XVI, the International Theological Commission (ITC) published a document called “The Hope of Salvation for Infants Who Die Without Being Baptized.” It is important to realize that the ITC is not an organ of the Magisterium, but a committee of scholars valued by the Holy See. Its documents are meant to promote debate in the Catholic academy, but they are worth only what their arguments are worth. They are not magisterial texts, which would have some prior claim on our assent. The authors of the 2007 document note that it has long been “common doctrine” that infants who die unbaptized do not enter the beatific vision, but they think that this teaching gives rise to “numerous pastoral problems,” and so, despite the Church’s tradition, they wish to replace it with a hope that all these souls will in fact be glorified. A major weakness of the document is that it gives no serious consideration to the meaning and authority of the Florentine definition, which it alludes to only in a footnote. (emphasis mine)
Father Crean accurately points out a weakness of that document. I will point out one of its strengths: While in its last part it expresses a “hope” for the salvation of unbaptized infants, in its earlier parts, it documents the historical continuity of the traditional, (i.e., contrary) teaching in favor of Limbo.
Many will no doubt argue with the provocative title I gave this posting. Father Crean does an excellent job of showing that, while the word Limbo makes its way into only one dogmatic statement of the Magisterium (which is quoted on this site), the concept of Limbo is clearly defined dogmatically in Florence. He also speculates as to why Florence shied away from the use of the word while defining the concept.
Please read the article. Though brief, it goes a long way in answering the modern mania to relegate Limbo to the memory hole.