Our task, our primary goal, is not a discussion of any particular articles of the fundamental doctrine of the Church, nor that we repeat at greater length what has been repeatedly taught by the Fathers and by ancient and modern theologians, and which we think to be well known and familiar to all. For this a Council was not necessary. But at the present time what is needed is that the entire Christian teaching with no part omitted, be accepted by all in our time with fresh zeal, with serene and tranquil minds, as it still shines forth in the Acts of the Council of Trent and First Vatican Council. It is necessary that as all sincere cultivators of the Christian, Catholic, and apostolic reality ardently desire that the same doctrine be more fully and deeply understood that consciences be more deeply imbued and formed by it; it is necessary that such certain and immutable doctrine, to which we owe the obedience of faith, be scrutinized and expounded with the method that our times require. One thing is the deposit of faith and the truths contained in our venerable doctrine, another thing is the way they are announced, with the same meaning and the same content.
The text of Paul VI to which he refers, from the Wednesday audience of November 26, 1969, the last given before the Novus Ordo Missae came into general use on the following Sunday. (full text here.)