"The Ordination of Women: Infallibly Taught?" by Peter Burns, S. J.

http://astro.temple.edu/~arcc/burns.htm



..."Ordinatio sacerdotalis was declared by the Sacred Congregation for the Doctrine of the Faith to be a teaching act that was, and I quote, "not itself infallible." It was made explicit by the Congregation at the press conference held to publicize its Responsio ad dubium (relating to the Apostolic Letter) that ordinatio sacerdotalis was NOT an exercise of the pope's extraordinary infallible magisterium. ..


Although it conceded that the teaching contained in OS was not infallibly taught in virtue of the extraordinary papal magisterium, the CDF nonetheless gave its opinion that the teaching contained in OS was an infallibly taught doctrine in virtue of the ordinary magisterium of the Church as explicated in section 25 of Lumen gentium, the Dogmatic Constitution on the Church issued by Vatican II. That is, it was the opinion of the CDF that the doctrine had already, prior to and independently of OS, been taught infallibly by the College of Bishops in union with the pope as a teaching that must be definitively held (tenenda definitive) to belong to the deposit of faith. This mode of infallible teaching requires a clear, constant teaching on the part of the bishops as a moral whole that some point of doctrine has been divinely revealed (cf. Lumen gentium, 25)

There are 3 modes of infallible teaching:
an infallible ex cathedra definition by the pope (this need not follow a consultation with the College of Bishops, though this was the practice in the two clear cases of such a definition, the Immaculate Conception (Pius IX, 1854) and the Assumption of the BVM (Pius XII, 1950);


a solemn definition by a valid ecumenical council of the Church (e.g. the dogmatic decrees on the divinity and humanity of Christ etc, at Nicaea and Chalcedon and many other dogmas); and


a constant teaching, not with any specific definition or formula, by the College of Bishops while dispersed around the world, but maintaining communion with the pope, that a doctrine belongs to the deposit of faith and must be held definitively as such by all the faithful (an example would be the Resurrection of Christ). What the CDF said clearly enough was that OS contains a teaching which has been infallibly taught in the third of these modes. It also EXPLICITLY said that OS was NOT an instance of the first of these modes. And obviously the matter has not been solemnly defined in the second (conciliar) mode.That is the official Catholic position. I won't enter any dispute about this, because it's silly to argue about facts. And these are the facts about the official position of the Church. They can readily be verified by reading the documents issued by the CDF and the relevant issues of L'Osservatore Romano..."

"Now, the next question we must ask: is the CDF's opinion about the infallible status of the doctrine itself infallible? The answer is definitely NO. Why? Because NOTHING the CDF says is EVER infallibly said. The CDF is not the pope speaking ex cathedra, nor is it a valid ecumenical council, nor is it the College of Bishops in union with the pope. The only way a doctrine can be infallibly taught is by one of the 3 modes of infallible teaching I described above. The CDF can give an opinion about if or when a teaching has been infallibly taught, but ITS OPINION IS ITSELF ALWAYS FALLIBLE. THE CDF IS NOT ENDOWED WITH INFALLIBILITY. Of course, the CDF can state a doctrine which has been infallibly taught. But so can anyone. If I simply repeated an infallibly defined doctrine, such as the Assumption, I would say something which has been infallibly taught. I would be uttering an infallible truth. But I would not be infallible then or ever. Same with the CDF. Its opinion on this as on any other matter is fallible. "