A Position That Hardened, Then Loosened, by Decree

Article one sets the typology out as live philosophical options. Within Christianity specifically, the exclusivist end of the spectrum was not always a position argued for; for long stretches it was official teaching stated with escalating force, and its later loosening happened by specific documents rather than by drift.

The formula extra ecclesiam nulla salus, no salvation outside the church, is associated with Cyprian of Carthage in the third century, arguing against the validity of baptism performed by schismatics. The Council of Florence's 1442 bull Cantate Domino stated the position in its starkest form, holding that those outside the Catholic Church, including non-Christians, Jews and heretics, cannot share in eternal life unless joined to it before death. That is about as hard a conciliar exclusivism as exists in Christian history.

The Second Vatican Council's 1965 declaration Nostra Aetate reversed the practical thrust without repudiating the formula outright, affirming that other religions often reflect a ray of the truth and calling for dialogue and mutual respect rather than for conversion as the sole legitimate relationship. Lumen Gentium, the same council's dogmatic constitution, is where the inclusivist reading article one describes, that those who through no fault of their own remain outside yet sincerely seek God may attain salvation, was given magisterial standing. The doctrine did not change its wording so much as its emphasis moved from the sentence's first half to its qualifications, which is exactly the kind of shift that lets a body claim continuity while visibly changing course.