At the same time every Council is an act of the supreme Magisterium of the Church. Magisterium signifies teaching based on authority, a teaching which is the mission of the Apostles and their successors: it is part of their function and an essential task. This teaching is concerned essentially with questions of faith and morals: what men and women should believe in and in what manner, and hence how they should live according to their faith. The doctrine of faith and morals (doctrina fidei et morum)
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