Synod of Bishops

Paul VI established the Synod of Bishops by the motu proprio Apostolica Sollicitudo on 15 September 1965, while the Second Vatican Council was still sitting. The timing is the explanation. The Council had gathered the world's bishops in Rome for four sessions and had put a great deal of weight on collegiality, the idea that the bishops together with the pope share responsibility for the whole church; and the Council was about to end. The Synod was the mechanism by which something of that gathering would continue without keeping two and a half thousand bishops permanently in Rome.

Its assemblies come in three kinds. Ordinary general assemblies meet at intervals of a few years on a topic chosen by the pope, with most members elected by the episcopal conferences of the world. Extraordinary assemblies are smaller and quicker, for matters needing prompt attention. Special assemblies cover a region, and those on Africa, on Lebanon, on the Middle East and on the Amazon have each addressed a set of questions that a global assembly would have handled thinly.

The working method is stable: a preparatory outline, a consultation, a working document, then the assembly itself, and afterwards a post-synodal apostolic exhortation issued by the pope, which is the document that actually carries teaching weight.

The Synod was consultative by design, and for fifty years the pattern held: the assembly discussed and voted on propositions, and the pope wrote the document. Francis changed the instrument twice. The apostolic constitution Episcopalis Communio, issued in 2018, provided that the final document of an assembly, if the pope approves and orders its publication, participates in his ordinary magisterium, which gives an assembly text a standing it did not previously have. The same constitution formalised a consultation phase reaching into dioceses before an assembly meets.

The synod on synodality, running from 2021 through assemblies in 2023 and 2024, applied that at full stretch, with parish and diocesan listening stages, national syntheses and continental assemblies feeding the working document. At the 2023 assembly, for the first time, a number of members who were not bishops, including women, were voting participants alongside the bishops. The change was made by the pope's decision and was reported and argued about worldwide, and it is the sharpest single illustration of what the instrument now is.

None of this makes it a parliament. The pope convokes it, sets its topic, appoints a share of its members and decides what follows from it. It is also not the same institution as the standing holy synods of the Eastern churches, which govern their churches rather than advising a bishop of Rome.