11 October 1962, opening exhortation from Pope John XXIII:
…It is sufficiently clear, Venerable Brethren, what are the parts which, as regards doctrine, are entrusted to the Ecumenical Council.
Indeed, the Twenty-First Ecumenical Council — which avails itself of the effective and highly esteemed assistance of those who excel in knowledge of the sacred disciplines, in the exercise of the apostolate, and in right and orderly conduct — wishes to hand down the Catholic doctrine entire, not diminished, not distorted, [integram, non imminutam, non detortam] which, although amid difficulties and controversies, has become as it were the common patrimony of mankind. This is not, indeed, pleasing to all; [!] nevertheless, to all who are endowed with good will it is proposed as a ready and most abundant treasure.
Yet it is not our task merely to guard this precious treasure, as though we were concerned only for antiquity; rather, let us now, with eager spirit and without fear, apply ourselves to the work which our age requires of us, pursuing the road which the Church has followed for almost twenty centuries.
Nor does our work look, as though to its primary end, to disputing certain chief points of ecclesiastical doctrine, and thus to repeating at greater length those things which the Fathers and the theologians, ancient and recent, have handed down, and which we rightly think are not unknown to you but are fixed in your minds.
For, indeed, for the holding of such discussions alone there was no need that an Ecumenical Council be convoked. However, in the present circumstances it is necessary that the whole of Christian doctrine, with no part taken away, [nulla parte inde detracta] be received by all in our times with new zeal, with minds calm and peaceful, expressed in that accurate manner of conceiving and formulating words which shines forth especially from the acts of the Councils of Trent and Vatican I. It is necessary that, just as all sincere promoters of what is Christian, Catholic, and Apostolic earnestly desire, this same doctrine be more widely and more deeply known, and that minds be more fully imbued and shaped by it. It is necessary that this doctrine, certain and unchangeable, to which faithful obedience must be given, be examined and set forth according to that manner which our times demand.
For one thing is the very deposit of faith, that is, the truths contained in our venerable doctrine; another thing is the manner in which those same truths are expressed, though with the same sense and the same meaning. To this manner, indeed, much attention must be given, and patiently, if need be, labor expended upon it — namely, that there be introduced ways of presenting things which may be more in accord with the magisterium, whose character is above all pastoral.
At the beginning of the Second Ecumenical Vatican Council, it is manifest, as never before, that the truth of the Lord remains forever. For, while one age succeeds another, we see the uncertain opinions of men one after another taking the place of others, and errors arising often quickly vanish as a cloud driven away by the sun.
Against these errors the Church has at no time failed to stand opposed; she has often also condemned them, and indeed with the firmest severity.
(So far so good, right? Well, here begins The Troubles…)
As regards the present time, it pleases the Spouse of Christ [wait for it…] to employ the medicine of mercy rather than to take up the arms of severity; she judges that, more than by condemning, she ought to meet the needs of the present day by explaining her doctrine more abundantly in its power…
Thanks to Father Z for putting this up… read the whole thing here: https://wdtprs.com/2025/10/11-october-1962-pope-john-xxiii-solemnly-opened-the-second-vatican-council/