Lumen Gentium #25 reads: “This loyal submission of the will and intellect must be given, in a special way, to the authentic teaching authority of the Roman Pontiff, even when he does not speak ex cathedra in such wise, indeed, that his supreme authority be acknowledged with respect, and that one sincerely adhere to decisions made by him, conformably with his manifest mind and intention, which is made known principally either by the character of the documents in question, or by the frequency with which a certain doctrine is proposed, or by the manner in which the doctrine is formulated.”
It goes on: “The Roman Pontiff, head of the college of bishops, enjoys this infallibility in virtue of his office, when, as supreme pastor and teacher of all the faithful – who confirms his brethren in the faith (Lk. 22, 32) – he proclaims in an absolute decision a doctrine pertaining to faith or morals. For that reason his definitions are rightly said to be irreformable by their very nature and not by reason of the assent of the Church, is as much as they were made with the assistance of the Holy Spirit promised to him in the person of blessed Peter himself; and as a consequence they are in no way in need of the approval of others, and do not admit of appeal to any other tribunal. For in such a case the Roman Pontiff does not utter a pronouncement as a private person, but rather does he expound and defend the teaching of the Catholic faith as the supreme teacher of the universal Church, in whom the Church’s charism of infallibility is present in a singular way.”
Toast First to Conscience, Then to the Pope
Benedict, at a bishops workshop in Dallas, Texas, said in February 1991: “I would simply like to try to indicate the place of conscience in the whole of Newman’s life and thought… When the subject of Newman and conscience is raised, the famous sentence from his letter to the Duke of Nor fold immediately comes to mind: `Certainly, If I am obliged to bring religion into afterdinner toasts, (which indeed does not seem quite the thing), I shall drink – to the Pope, if you please, - still, to conscience first, and to the Pope afterwards.”
Benedict then clarified the ontological source of conscience, of the values of good and evil that are not principles but the consciousness of the experience of the ontological tendency of the being of man as imaging the triune God: “This means that the first so-called ontological level of the phenomenon conscience consists in the fact that something like an original memory of the good and true (both are identical) has been implanted in us, that there is an inner ontological tendency within man, who is created in the likeness of God, toward the divine. From its origin, man’s being resonates with some things and clashes with others. This anamnesis of the origin, which results from the godlike constitution of our being is not a conceptually articulated knowing, a store of retrievable contents. It is so to speak an inner sense, a capacity to recall, so that the one whom it addresses, if he is not turned in on himself, hears its echo from within. He sees: That’s it! That is what my nature points to and seeks…
“We can now appreciate Newman’s toast first conscience and then to the pope. The pope cannot impose commandments on faithful Catholics because he wants to or finds it expedient. Such a modern, voluntaristic concept of authority can only distort the true theological meaning of the papacy. The true nature of the Petrine office has become so incomprehensible in the modern age no doubt because we only think of authority in terms which do not allow for bridges between subject and object. Accordingly, everything which does not come from the subject is thought to be externally imposed. But the situation is really quite different according to the anthropology of conscience which we have tried to come to an appreciation of in these reflections. The anamnesis instilled in our being needs, one might say, assistance from without so that it can become aware of itself. But this `from without’ is not something set in opposition to anamnesis but ordered to it. It has maieutic function, imposes nothing foreign, but brings to fruition what is proper to anamnesis, namely, interior openness to the truth….
“The true sense of the teaching authority of the pope consists in his being the advocate of the Christian memory. The pope does not impose from without. Rather he elucidates the Christian memory and defends it. For this reason the toast to conscience indeed must precede t he toast to the Pope because without conscience there would not be a papacy. All power that the papacy has is power of conscience. It is service to the double memory upon which the faith is based and whish again and again must be purified, expanded, and defended against the destruction of memory which is threatened by a subjectivity forgetful of its own foundation as well as by the pressures of social and cultural conformity.”
 J. Ratzinger, “Key Note Address: `Conscience and Truth’ at the Proceedings of the Tenth Bishops’ Workshop, Dallas, Texas (1991) 14.