“Not Infallible” does not mean “Contains Errors.”

trict­ly speak­ing, “infal­li­bil­i­ty” cov­ers what­ev­er teach­ings fall under a divine guar­an­tee to be free from any pos­si­bil­i­ty of error. That does not mean, and nev­er meant, that non-infal­li­ble teachings—the Ordi­nary Mag­is­teri­um—do con­tain errors. Still less does it mean that the pope could under any cir­cum­stances teach heresy. Pope Pius XII says in Humani Gener­is 20:

Nor must it be thought that what is expound­ed in Encycli­cal Let­ters does not of itself demand con­sent, since in writ­ing such Let­ters the Popes do not exer­cise the supreme pow­er of their Teach­ing Author­i­ty. [In oth­er words, just because it’s not infal­li­ble does­n’t mean you can take it or leave it.] For these mat­ters are taught with the ordi­nary teach­ing author­i­ty, of which it is true to say: “He who heareth you, heareth me.”

That’s Luke 10:16 Pius is quot­ing. Even when a pope is teach­ing with ordi­nary author­i­ty, he is still teach­ing with the author­i­ty of Christ. He who hears you, hears me; he who rejects you, rejects me; he who rejects me, rejects the one who sent me.

Pius II con­tin­ues:

And gen­er­al­ly, what is expound­ed and incul­cat­ed in Encycli­cal Let­ters already for oth­er rea­sons apper­tains to Catholic doc­trine. But if the Supreme Pon­tif­fs in their offi­cial doc­u­ments pur­pose­ly pass judg­ment on a mat­ter up to that time under dis­pute, it is obvi­ous that that mat­ter, accord­ing to the mind and will of the Pon­tif­fs, can­not be any longer con­sid­ered a ques­tion open to dis­cus­sion among the­olo­gians”

Not even for ordi­nary teach­ings.

But the CDF, in Don­um Ver­i­tatis, expands this to include even the Mag­is­teri­um’s “inter­ven­tions in the pru­den­tial order.” Imag­ine that. (For Pope Pius IX con­demned, as a Mod­ernist error, the com­plaint that popes inter­fere in polit­i­cal mat­ters. That’s #23 on the Syl­labus. Tolle, lege.) Here’s the CDF in DV:

When it comes to the ques­tion of inter­ven­tions in the pru­den­tial order, it could hap­pen that some Mag­is­te­r­i­al doc­u­ments might not be free from all defi­cien­cies. [They might not be free from all.] Bish­ops and their advi­sors have not always tak­en into imme­di­ate con­sid­er­a­tion every aspect or the entire com­plex­i­ty of a ques­tion. But”—[Now pay atten­tion, dear read­er:]—“it would be con­trary to the truth, if, pro­ceed­ing from some par­tic­u­lar cas­es, one were to con­clude that the Church’s Mag­is­teri­um can be habit­u­al­ly mis­tak­en in its pru­den­tial judg­ments, or that it does not enjoy divine assis­tance in the inte­gral exer­cise of its mis­sion” (24).

Exact­ly. And the CDF takes care to spec­i­fy the nature of the “defi­cien­cies” that “might” creep in. “[I]n addi­tion to sol­id prin­ci­ples,” it says, ordi­nary teach­ings may include “cer­tain con­tin­gent and con­jec­tur­al ele­ments. It often only becomes pos­si­ble with the pas­sage of time to dis­tin­guish between what is nec­es­sary and what is con­tin­gent. … The the­olo­gian knows that some judg­ments of the Mag­is­teri­um could be jus­ti­fied at the time in which they were made, because while the pro­nounce­ments con­tained true asser­tions and oth­ers which were not sure, both types were inex­tri­ca­bly con­nect­ed. Only time has per­mit­ted dis­cern­ment and, after deep­er study, the attain­ment of true doc­tri­nal progress” (24).

So for exam­ple, the Church has recent­ly come to under­stand that the lic­it­ness of the death penal­ty is con­tin­gent upon whether it is nec­es­sary to pro­tect soci­ety. St. John Paul II points out (Evan­geli­um Vitae 56) that, with improve­ments in prison secu­ri­ty, the death penal­ty is not nec­es­sary in the way it once was. This does not mean that either the pri­or teach­ing or the cur­rent teach­ing is “in error.”

And the Church is very clear that Catholics are bound to the Church’s authen­tic Mag­is­teri­um even when it’s not defin­i­tive. (In fact, Pius IX in Syl­labus 22 con­demned as a heresy the idea that Catholics are bound “to those things only which are pro­posed to uni­ver­sal belief as dog­mas of faith by the infal­li­ble judg­ment of the Church.) Lumen Gen­tium 25 says: “[R]eligious sub­mis­sion of mind and will must be shown in a spe­cial way to the authen­tic mag­is­teri­um of the Roman Pon­tiff, even when he is not speak­ing ex cathe­dra.” This lan­guage is repeat­ed in the Cat­e­chism of the Catholic Church, the Pro­fes­sion of Faith, and Canon 752.

If the Church is going to bind Catholics to the full Magisterium—even the tech­ni­cal­ly non-infal­li­ble part—it makes no sense at all to think that a pope could teach actu­al heresy. The impos­si­bil­i­ty of any such thing is con­se­quent upon the Holy Spir­it’s pro­tec­tion of the Church from error and its promise to guide the Church into all truth (John 16:13).

Vat­i­can I defines the con­di­tions for infal­li­bil­i­ty, but implic­it in that teach­ing is the guar­an­tee that a pope can’t bind the Church to heresy. And if Catholics are bound even by ordi­nary teach­ings, it fol­lows they can’t con­tain heresy either. To sug­gest oth­er­wise is false.

•••

I bring this up because every time I write an arti­cle like my last one, invari­ably some­one shows up to say that I don’t know what infal­li­bil­i­ty is or think every­thing a pope says is infal­li­ble. Fact is, not only have I nev­er said that every­thing a pope says is infal­li­ble, I’ve express­ly denied it.

Here I am on Novem­ber 24, 2015:

[Infal­li­bil­i­ty] does not mean that every­thing a pope says, or every opin­ion of the pope, is infal­li­ble. The pope must be speak­ing ex cathe­dra. A Wednes­day audi­ence, or a papal inter­view, are not infal­li­ble. The pope must be speak­ing on a ques­tion of faith or morals. The pope’s opin­ion about a sci­en­tif­ic the­o­ry is not infal­li­ble. The pope’s opin­ion of the Red Sox is not infal­li­ble.

Here I am on April 5, 2017: “Things the pope says in an inter­view with the press are not Mag­is­te­r­i­al.”

Here I am on Octo­ber 15, 2017: “I have nev­er tak­en the posi­tion that every­thing a pope says is infal­li­ble. I defy you to find me mak­ing any such argu­ment, at any time, any­where. Search as long as you please and report back to me.”

So I know that per­fect­ly well. What I have said (if my actu­al views mat­ter to any­one) is that a pope can’t teach heresy [one / two]. And what I have said is that it does­n’t mat­ter whether a teach­ing is infal­li­ble or not as long as it’s author­i­ta­tive. And inci­den­tal­ly, the Church also says this. Here’s one place it says so—Don­um Ver­i­tatis 17:

All acts of the Mag­is­teri­um derive from the same source, that is, from Christ who desires that His Peo­ple walk in the entire truth. For this same rea­son, mag­is­te­r­i­al deci­sions in mat­ters of dis­ci­pline, even if they are not guar­an­teed by the charism of infal­li­bil­i­ty, are not with­out divine assis­tance and call for the adher­ence of the faith­ful.

It is inco­her­ent to say that just because a teach­ing is not infal­li­ble, “divine assis­tance” is going to per­mit heresy to creep in. It can’t hap­pen, not unless the Church has utter­ly erred in its under­stand­ing of Mag­is­te­r­i­al teach­ing author­i­ty con­se­quent upon John 16:13, John 21:15, and 1 Tim­o­thy 3:15, to name just three.