"The task of giving an authentic interpretation of the Word of God, whether in its written form or in the form of Tradition, has been entrusted to the living teaching office of the Church alone. Its authority in this matter is exercised in the name of Jesus Christ." 47 This means that the task of interpretation has been entrusted to the bishops in communion with the successor of Peter, the Bishop of Rome.

The mission of the Magisterium is linked to the definitive nature of the covenant established by God with his people in Christ. It is this Magisterium's task to preserve God's people from deviations and defections and to guarantee them the objective possibility of professing the true faith without error. Thus, the pastoral duty of the Magisterium is aimed at seeing to it that the People of God abides in the truth that liberates. To fulfill this service, Christ endowed the Church's shepherds with the charism of Infallibility in matters of faith and morals. the exercise of this charism takes several forms:

The Magisterium of the Pastors of the Church in moral matters is ordinarily exercised in catechesis and preaching, with the help of the works of theologians and spiritual authors. Thus from generation to generation, under the aegis and vigilance of the pastors, the "deposit" of Christian moral teaching has been handed on, a deposit composed of a characteristic body of rules, commandments, and virtues proceeding from faith in Christ and animated by charity. Alongside the Creed and the Our Father, the basis for this catechesis has traditionally been the Decalogue which sets out the principles of moral life valid for all men.