Can. 750 §1. A person must believe with divine and Catholic faith all those things contained in the word of God, written or handed on, that is, in the one deposit of faith entrusted to the Church, and at the same time proposed as divinely revealed either by the solemn magisterium of the Church or by its ordinary and universal magisterium which is manifested by the common adherence of the Christian faithful under the leadership of the sacred magisterium; therefore all are bound to avoid any doctrines whatsoever contrary to them.
§2. Each and every thing which is proposed definitively by the magisterium of the Church concerning the doctrine of faith and morals, that is, each and every thing which is required to safeguard reverently and to expound faithfully the same deposit of faith, is also to be firmly embraced and retained; therefore, one who rejects those propositions which are to be held definitively is opposed to the doctrine of the Catholic Church.
Can. 752 Although not an assent of faith, a religious submission of the intellect and will must be given to a doctrine which the Supreme Pontiff or the college of bishops declares concerning faith or morals when they exercise the authentic magisterium, even if they do not intend to proclaim it by definitive act; therefore, the Christian faithful are to take care to avoid those things which do not agree with it.
In enquiring into the nature of these demands upon assent, one should also take a look at the motu proprio of John-Paul II ad tuendam fidem which cast these canons into their current form. Certainly one must also read carefully the doctrinal commentary on ad tuendam fidem produced by the Congregation for the Doctrine of the Faith. In this latter, levels within the hierarchy of truths are identified (corresponding to the three paragraphs of the canons above) and the sanctions appropriate to denial of these truths are laid out. So, unsurprisingly perhaps, a denial of a revealed dogma of the faith falls under the sanction of heresy. A denial of a teaching associated with the second paragraph would result in the denier removing themselves from communion with the Church. So, for example, one obstinately claiming abortion to be licit would be a heretic; one obstinately claiming the possibility of women’s ordination would put themselves outside the communion of the Church.
Such claims on the assent required to the teaching of the Church may very well seem strange to modern sensibilities; surely a docile response to authority alone is being demanded? Why does the Church make such demands? On what authority does it claim such authority?
The beginnings of an answer to such questions might be best expressed by the teaching of the second Vatican council; the Church’s authority in making these demands lies with the will of Christ:
“For the Catholic Church is by the will of Christ the teacher of truth. It is her duty to proclaim and teach with authority the truth which is Christ and, at the same time, to declare and confirm by her authority the principles of the moral order which spring from human nature itself”. Dignitatis humanae 14.
In these posts on “Authority”, I intend to attempt answers to such questions as these. To do so, I will meander far and wide; please join me on the journey. Perhaps you might offer smoother roads than I can find or identify higher hurdles that I should cross.