§1. The Church, to which Christ the Lord has entrusted the deposit of faith so that with the assistance of the Holy Spirit it might protect the revealed truth reverently, examine it more closely, and proclaim and expound it faithfully, has the duty and innate right, independent of any human power whatsoever, to preach the gospel to all peoples, also using the means of social communication proper to it.
§2. It belongs to the Church always and everywhere to announce moral principles, even about the social order, and to render judgment concerning any human affairs insofar as the fundamental rights of the human person or the salvation of souls requires it.
§1. All persons are bound to seek the truth in those things which regard God and his Church and by virtue of divine law are bound by the obligation and possess the right of embracing and observing the truth which they have come to know.
§2. No one is ever permitted to coerce persons to embrace the Catholic faith against their conscience.
§1. By virtue of his office, the Supreme Pontiff possesses infallibility in teaching when as the supreme pastor and teacher of all the Christian faithful, who strengthens his brothers and sisters in the faith, he proclaims by definitive act that a doctrine of faith or morals is to be held.
§2. The college of bishops also possesses infallibility in teaching when the bishops gathered together in an ecumenical council exercise the magisterium as teachers and judges of faith and morals who declare for the universal Church that a doctrine of faith or morals is to be held definitively; or when dispersed throughout the world but preserving the bond of communion among themselves and with the successor of Peter and teaching authentically together with the Roman Pontiff matters of faith or morals, they agree that a particular proposition is to be held definitively.
§3. No doctrine is understood as defined infallibly unless this is manifestly evident.
§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 firm-ly 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. 751 Heresy is the obstinate denial or obstinate doubt after the reception of baptism of some truth which is to be believed by divine and Catholic faith; apostasy is the total repudiation of the Christian faith; schism is the refusal of submission to the Supreme Pontiff or of communion with the members of the Church subject to him.
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.
Can. 753 Although the bishops who are in communion with the head and members of the college, whether individually or joined together in conferences of bishops or in particular councils, do not possess infallibility in teaching, they are authentic teachers and instructors of the faith for the Christian faithful entrusted to their care; the Christian faithful are bound to adhere with religious submission of mind to the authentic magisterium of their bishops.
Can. 754 All the Christian faithful are obliged to observe the constitutions and decrees which the legitimate authority of the Church issues in order to propose doctrine and to proscribe erroneous opinions, particularly those which the Roman Pontiff or the college of bishops puts forth.
§1. It is above all for the entire college of bishops and the Apostolic See to foster and direct among Catholics the ecumenical movement whose purpose is the restoration among all Christians of the unity which the Church is bound to promote by the will of Christ.
§2. It is likewise for the bishops and, according to the norm of law, the conferences of bishops to promote this same unity and to impart practical norms according to the various needs and opportunities of the circumstances; they are to be attentive to the prescripts issued by the supreme authority of the Church.