The Doctrine of Papal Infallibility teaches that the Pope, when he teaches on matters that concern faith or morals to the whole Church with the intent that the faithful follow the opinion, is teaching infallibly. One of the biggest practical problems with this doctrine is the issue of earlier Popes contradicting later Popes. Whenever this occurs, the Catholic apologist is forced to come up with all sorts of excuses as to how the earlier pope was not speaking Ex Cathedra.
With reference to which particular we are not acting irregularly, if from the books, though not Canonical, yet brought out for the edifying of the Church, we bring forward testimony. Thus Eleazar in the battle smote and brought down an elephant, but fell under the very beast that he killed [1 Macc. 6, 46]…
I have heard two Catholic apologetic approaches to this problematic passage.
Father John Echert asserts that Gregory the Great was merely writing his own “private opinion.” This is a strange opinion giving that Gregory the Great said that he was bringing forth a quotation that was not Canon for the sake of edifying the Church at large. This is not mere private opinion. The obvious implication is that he was acting as shepherd to his flock and felt that they should know that non-Canonical books are still useful for teaching.
Catholic Matt asserts that Gregory the Great was not Pope yet when he wrote the passage in question. We can dispatch with this reasoning simply by saying that he still edited and essentially “published” (or the ancient equivalent) the book after becoming Pope. This shows that he intended to teach to the Church as a matter of doctrine concerning faith that certain books while not Canonical were, yet, edifying.
Both Father Echert and Catholic Matt also put forth the argument that Gregory the Great did not view that Deuterocanon quite up to par with the actual Canon, but still viewed them as Scripture. This defense is a little weak. The Council of Trent says, “But if any one receive not, as sacred and canonical, these same books entire with all their parts…contained in the old Latin Vulgate edition; and knowingly and deliberately despise the traditions aforesaid; let him be anathema.”
Clearly, Gregory the Great did not receive such books as Canonical for he wrote that they were not! However, being that he did not deliberately despise the books, and in fact quoted them as Scripture in several of his books, shows he would not have been anathematized.
However, not being anathematized is not good enough ultimately for the upholding of the doctrine of Papal Infallibility. Gregory the Great, theoretically, cannot contradict later supposedly infallible councils, while remaining infallible himself. In short, Echert and Matt cannot say that Gregory the Great and the Council of Trent had an identical view of the Deuterocanon, because by their own admission he did not view the Deuterocanon as equal to the rest of the Canon.
One final note: Gregory the Great’s view of the Canon is probably the view that all Christians should adopt. Protestants generally have done away with the Deuterocanon, calling it Apocrypha, while Catholics have put the Deuterocanon up to par with what I’ll call the “First Canon,” i.e. the undisputed Canonical books of the Bible. Neither position is correct.
I honestly believe that the whole answer is solved in what the term “Deuterocanon” even means. It’s a Canon of sorts, but secondary. The books are useful, but they do not carry the weight of the rest of Scripture. The Deuterocanon is referred to by Paul in Romans 9 and accurately prophesies Christ’s passion. To treat it as if it were completely uninspired would be foolish.