By Pope Paul VI: 30 June 1968
3. Likewise, we deem that we must fulfill the mandate entrusted by Christ to Peter, whose successor we are, the last in merit; namely, to confirm our brothers in the faith.(2) With the awareness, certainly, of our human weakness, yet with all the strength impressed on our spirit by such a command, we shall accordingly make a profession of faith, pronounce a creed which, without being strictly speaking a dogmatic definition, repeats in substance, with some developments called for by the spiritual condition of our time, the creed of Nicea, the creed of the immortal tradition of the holy Church of God.
4. In making this profession, we are aware of the disquiet which agitates certain modern quarters with regard to the faith. They do not escape the influence of a world being profoundly changed, in which so many certainties are being disputed or discussed. We see even Catholics allowing themselves to be seized by a kind of passion for change and novelty. The Church, most assuredly, has always the duty to carry on the effort to study more deeply and to present, in a manner ever better adapted to successive generations, the unfathomable mysteries of God, rich for all in fruits of salvation. But at the same time the greatest care must be taken, while fulfilling the indispensable duty of research, to do no injury to the teachings of Christian doctrine. For that would be to give rise, as is unfortunately seen in these days, to disturbance and perplexity in many faithful souls.