The apostles had a unique role as the recipients of God’s revelation in Jesus. By the gift of the Spirit, Jesus ensured that they would not make mistakes in believing. In their recognition of God’s revelation, they were infallible—that is, the very possibility of error was excluded. But God’s revelation was not just for the apostles. They were commissioned to spread it to all humankind. Founded on the apostles and continuing their mission, the Church as a whole also enjoys infallibility. Individual members can err about what is and is not included in revelation, but the Church as a whole cannot.
The books of Scripture, which express the Church’s faith, have God as their author; they contain his word. Therefore, whatever the sacred writers assert must be recognized as true. Fundamentalism assigns the value of divine truth to the propositions each individual extracts from the Bible; theological liberalism attempts to judge the truth of God’s word by some extrinsic standard. In contrast with both, Catholics trust that all propositions asserted by the sacred writers are true, but rely on the discernment of the Church in interpreting the Bible.
Scripture contains some inerrant moral teachings—namely, those asserted by the inspired writers. Because most moral norms are nonabsolute and can be commended with varying degrees of force, the presence in the Bible of norms which admit of exceptions or seem unsound does not argue against the truth of those norms proposed as certainly true and exceptionless. Specifically, the Ten Commandments, though needing interpretation and development, have the status of fundamental, revealed moral truth.
As successors of the apostles, bishops, in communion with one another and the pope, are authorized spokesmen for Jesus; their prophetic role is called the “magisterium.” Since individual members can err in belief, the infallibility of the Church evidently needs such an instrument. The magisterium has authority to judge what belongs to revelation. Its authority is not that of scholarly competence or administrative power, but a participation in the authority of Jesus’ communication of the personal truth of God.
Vatican II clearly states the criteria for an infallible exercise of the magisterium by the bishops engaged in their ordinary work of teaching. They must be in communion with one another and the pope; they must teach authoritatively on a matter of faith and morals; they must teach with virtual unanimity; and they must propose a judgment to be held definitively. To deny that the bishops teach infallibly under these conditions is to deny either that the Church is infallible or that they really exercise the role of apostolic leadership instituted by Jesus.
There is a substantial body of common Catholic moral teaching in which some kinds of acts are condemned absolutely, without any exception. A constant consensus, broken only since 1960, exists about such matters among Catholic theologians in modern times. It is expressed, among other places, in works whose authorized use—for training priests—shows that they contain moral teaching universally proposed by the bishops. The evidence further indicates that on many specific points this moral teaching was proposed definitively. Where Scripture and this teaching clearly coincide, there is no room for doubt that the ordinary magisterium has infallibly proposed a revealed truth. In other cases, its exercise clearly meets Vatican II’s criteria for infallible teaching.
But how is one to regard teaching which could be recognized as infallibly proposed, except that the entire college of bishops has not agreed in one judgment? The question is particularly relevant when bishops confront new questions and teach what has not been taught before. Mistakes are possible, yet the faithful must accept such teaching. Here what Vatican II says about “religious assent” comes into play.
Even in such cases, where a teaching might possibly be erroneous, it also might possibly belong to revealed truth. This latter possibility cannot be ignored, and a faithful Catholic will of course be ready to accept in faith anything which turns out to be a revealed truth. This conditioned disposition to assent, together with one’s acceptance with divine faith of the episcopal or papal office as divinely given and accompanied by grace, leads one to religious assent: a Christian act of human faith grounded in divine faith itself.
Because no systematic moral theory can settle any issue with complete certainty by experience and purely rational analysis, experience and reason not illumined by faith cannot undercut the moral certitude of Catholics in accepting the teaching of the bishops and pope. There will be no cogent reason not to accept their teaching except some clearer claim of faith itself. It may happen that one or several bishops become firmly convinced of an erroneous doctrine and propose it as certain; the faithful can then look to the Holy See for clarification. In the case of papal teaching, however, there is little chance of its being undercut by a superior theological source.