(There is no such thing.) Some theologians on the far right, such as Fr. Chad Ripperger, claim that the universal and constant consensus of Catholic theologians is to be considered infallible. They cite Tuas Libenter by Pope Pius IX in support of this claim. Here is the offending passage:
“In fact, even if it were a matter of that obedience that is concretely due to divine faith, this obedience should not be limited to the truths expressly defined by decrees of the Ecumenical Councils or the Roman Pontiffs and of this Apostolic See, but must also extend to the truths which the ordinary magisterium of the whole Church dispersed through the world hands on as divinely revealed, and which therefore the universal and constant consensus of Catholic theologians holds to be a matter of faith.”
What is infallible? Truths taught by (1) Conciliar Infallibility, (2) Papal Infallibility, and (3) the ordinary and universal Magisterium. The role of the consensus of theologians is merely to recognize and point out to the faithful which teachings fall under the ordinary and universal Magisterium. The theologians are not exercising infallibility. Their consensus is not infallible. They are merely recognizing infallible teachings of the Pope and the Bishops under the ordinary and universal Magisterium.
When Pope Saint Paul VI asked for the opinion of theologians, a group chosen by the Roman Pontiff!, on contraception, what did he get? The majority opinion was in grave error, proposing to allow married persons to use contraception. What was the majority opinion about the conception of Mary (at a certain point in time about 700 years ago)? They had the wrong idea, including St. Thomas and St. Albert.
Theologians often disagree. Limiting the idea of consensus only to certain theologians, the good ones, the orthodox ones, the ones with certain credentials, the scholastics from a certain time period, etc. is absurd. There is no support in Sacred Tradition or Sacred Scripture for such an infallibility. Jesus’ rebuke of the scribes is sufficient in itself to disprove this claim of infallible consensus of theologians.
What about the claimed infallibility of the consensus of all believers?
“The entire body of the faithful, anointed as they are by the Holy One, cannot err in matters of belief. They manifest this special property by means of the whole peoples’ supernatural discernment in matters of faith when ‘from the Bishops down to the last of the lay faithful’ they show universal agreement in matters of faith and morals.” [Lumen Gentium 12]
This type of infallibility is of the Living Tradition. And note that it includes all the Bishops, with the Bishop of Rome certainly. So we have the infallibility of Sacred Tradition, of Sacred Scripture, and the three modes of infallibility of the Magisterium. There is no infallible consensus of theologians.
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