This quote (which makes sense to me) is attributed to a Fr. Hunwicke here: https://www.suscipedomine.com/forum/index.php?topic=10172.0"I have some queries which are genuinely queries. My mind really is not made up regarding the Infallibility of an act whereby the Roman Pontiff 'canonises'; and the probably but certainly related question of whether a de fide assent is required. I shall be entirely capricious in binning comments which just rant, especially if they are preoccupied with the canonisations due next April. I assume that everybody with an interest in this subject knows exactly what the Vatican I text of Pastor aeternus said and did not say about Papal infallibility. It is useful to have read parts of Benedict XIV's De Beatificatione et Canonizatione, and Liber1 Caput LXV really is required reading; it can be found by googling Benedicti papae XIV Doctrina de Servorum Dei beatificatione et ..., and then scrolling down to pages 55-56 (42-43 in the printed book which Google copied). It was written before the election of Prospero Lambertini to the See of Rome.
Theologians of distinction can be listed who have taught that Canonisation is an infallible act of the Papal Magisterium.
But, with regard to those who wrote before 1870, is there not a prior question that has to be asked? The Church had then not defined (i.e. put limits, 'fines', to) the dogma of Papal Infallibility. The terms of Pastor aeternus are (to the chagrin of Manning and the palpable relief of Newman) extremely limited.
Therefore, can we be sure that those earlier theologians really were categorising canonisation as infallible in the sense of the word infallible as defined with all the limitations of the 1870 decrees? Or, because of the limits imposed by that definition, might they have used a different term had they needed to develop their arguments within the confines of what Pastor aeternus lays down? Is this why Benedict XIV accepts the possibility of arguing that what a Roman Pontiff decrees may be infallible, but still not be de fide? After 1870, I surmise, that possibility may not be open to us: because the scope and function of the term infallibilis have changed to imply that a proposition is of faith. Am I right?
In assessing the arguments of such pre-1870 writers, should we pay attention to the general extent which they assert when talking about the authority of the Roman Pontiff? That is: if a writer is generous in his estimate of the fields to which papal infallibility extends, should we be less willing to assume that he is writing in terms of something like the limited 1870 definition, than we would be when considering a writer who is very much more sparing and circuмspect in associating infallibility with papal interventions?
As a consequence of this, when we turn to theologians who wrote later than 1870, and who argued that papal canonisations are infallible, should we not subtract from the arguments with which they sustain their conclusions the mere citation, qua authorities, and without further discussion, of those earlier theologians?
In other words, should not the event of 1870 have the effect of pruning back some previous theologically luxuriant growths?...
Finally: S Thomas held that canonisation was medium inter res fidei, et particulares; and Benedict XIV concludes his discussion of this matter by saying that plures magni nominis auctores deny that an act of canonisation is de fide; gives a fair wind to their arguments; then summarises the arguments of those, inferioris notae doctores, who affirm that it is de fide; concludes by saying Utraque opinio in sua probabilitate relinquenda videtur, donec Sedes Apostolica de hac re judicium proferat. Benedict XIV went on to give his own private opinion as favouring the positive thesis (canonisations are of faith), but added "But before a judgement of the Apostolic See, it does not seem that the mark of heresy should be branded onto the contrary opinion."And in 1998, the motu proprio Ad tuendam fidem of B John Paul II was accompanied by a Commentary written by the CDF and signed by its Cardinal Prefect. Paragraph 6 of this, combined with paragraphs 8 and 11, appears to lead to the conclusion that canonisations are to be given the same "full and irrevocable assent" as that required by the Creeds and the doctrinal definitions of Ecuмenical Councils and of Roman Pontiffs speaking ex cathedra. Have I understood this correctly? Would this be "a judgement of the Apostolic See" as described by Benedict XIV? What is the Magisterial status of a dicasterial 'Commentary'?
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And I have a prejudice against potentially causing people problems of conscience by telling them that something is of divine Faith when it might not be. And it potentially damages the august authority of the Sovereign Pontiff to be rash in spraying the I-word too liberally around ... a point which poor Manning never grasped."