ROME — In his 1947 classic “Civilization on Trial,” here’s how the legendary Arnold Toynbee described what historians are really after — among other things, thereby providing the best distinction ever delivered in the English language between journalism and history.

“The things that make good headlines are on the surface of the stream of life, and they distract us from the slower, impalpable, imponderable movements that work below the surface and penetrate to the depths,” Toynbee wrote. “But it is really these deeper, slower movements that make history, and it is they that stand out huge in retrospect, when the sensational passing events have dwindled, in perspective, to their true proportions.”

The Vatican beat at the moment provides a classic example of that contrast, as news outlets and pundits this week are consumed with Pope Francis’ latest use of off-color language to refer to gays, while the real movement of history lies instead in a new, nearly 150-page tome issued by the Dicastery for Promoting Christian Unity and titled “The Bishop of Rome: Primacy and Synodality in the Ecumenical Dialogues and in the Responses to the Encyclical Ut Unum Sint” (“That They May Be One”).

If the Christian Humpty Dumpty is ever put back together again — meaning, if the divided Christian family is ever reunified — the issuance of this document almost certainly will be remembered as a milestone moment along that path.

In effect, the document takes stock of where things stand 30 years after the late St. Pope John Paul II issued Ut Unum Sint, a landmark encyclical in which he invited other Christians to join Catholics in reimagining the exercise of the papacy to make it a force for unity rather than a lightning rod of division — what John Paul memorably called a “service of love recognized by all concerned.”

The new document synthesizes roughly 30 responses to Ut Unum Sint collected over the years from different Christian denominations and organizations, as well as the results of some 50 ecumenical dialogues that have taken up the question of papal primacy.

Summing up, the document suggests broad agreement on at least three basic points.

First, everybody more or less agrees on the need for some sort of unifying force at the universal level of Christianity. To put it differently, if we didn’t have a papacy, we’d have to invent it, though people may disagree strongly over what it should look like.

Second, there’s a broad sense that Catholic teaching about papal primacy needs to be revisited, especially that of Vatican I, the council which proclaimed the dogma of papal infallibility. The idea is to distinguish what’s essentially about that teaching, as opposed to what may have been conditioned by the exigencies of a particular historical moment.

Third, there’s also broad consensus that the way forward lies in exploring the relationship among “everybody, some and one,” meaning, respectively, synodality as a process involving all the stakeholders in Christianity, collegiality as a sense of shared authority among bishops, and papal primacy as the ultimate point of reference for the unity of the church.

This may all seem abstract and academic, but it’s vital prolegomena to any future prospect of overcoming Christianity’s historical divisions.

Boiling it all down, it’s a common-sense instinct that somebody has to be in charge, coupled with the political reality that the kind of authority invested in that leader, and the ways in which they’re able to exercise it, need to be hammered out clearly if the system’s going to hold up over time.

In presenting the document, much was made of Pope Francis’ own ecumenical teaching and gestures, especially his insistence on synodality as a constitutive element of the Church. The Secretary General of the Synod Cardinal Mario Grech of Malta, argued that the experience of synods under Francis “demonstrate how it could be possible to arrive at an exercise of primacy at an ecumenical level.”

One practical suggestion is the idea of greater synodality ad extra, meaning outside the Catholic Church, in the form of regular consultations among the leaders of the various Christian denominations — sort of a G7, if you like, of heads of churches instead of heads of state.

For all the promise of the new document, however, there are at least a couple of questions it leaves hanging, and which will have to be addressed in conversations going forward.

First, the most divisive issues in Christian life today aren’t just about who does the teaching, but what it is they teach — in other words, it’s not just about authority, but also doctrine.

This truth came home clearly in the ferment over Fiducia Supplicans, the Vatican’s controversial document authorizing blessings of persons in same-sex unions, which caused the Coptic Orthodox Church to suspend its dialogue with Catholicism and prompted the Russian Orthodox to declare that Fiducia represents “a sharp deviation from Christian moral teaching.”

How to ensure a baseline of agreement on core doctrinal principles, while also allowing individual churches to express their own language and pastoral practice, will remain a core ecumenical challenge regardless of how papal primacy ends up being resolved.

Second, there’s the matter of whether Francis’ own exercise of primacy is consistent with his rhetoric on synodality.

His two synod gatherings on synodality, after all, were widely expected to deal with the hot-button matters of blessing same-sex unions and women deacons, and indeed there was considerable conversation on both matters during the first edition last October. Yet in the interim before the concluding assembly this October, Francis preemptively has taken both issues off the table, first by issuing Fiducia and then by telling CBS he has no intention of moving on the diaconate.

Francis has also issued more motu proprio than all his recent predecessors combined, amending Church law at will: he staged a trial of a cardinal and nine other defendants which at least some observers believe ignored basic principles of due process; he’s run roughshod over traditional structures of governance in the Vatican, personalizing the papacy to a new degree; and he’s ignored the pleas of liturgical traditionalists for space to celebrate the Latin Mass, despite his repeated insistence that the Church must include “everybody, everybody, everybody.”

If that’s the Catholic notion of synodality, some ecumenical observers may be tempted to think, then it just seems like the imperial papacy under another guise.

Those thorny matters weren’t resolved by the new document, and will hang over ecumenical conversation for some time to come. Yet few would dispute that the ecumenical cause seems strong after “The Bishop of Rome” than before — and that, all by itself, probably is enough to classify it as one of Toynbee’s “slower, impalpable, imponderable movements” that make history.