The Latin word magisterium indicates the action of the magister, and this was true not only in classical Latin for teaching but for all forms of art (the master of the ship, the master blacksmith, master of an art or a craft). In the Middle Ages the word magister begins to be used in a narrower sense refers to teaching: eg Peter Lombard is the magister sententiarum, the "master of judgments."

In the modern era, at least in Catholic circles, the word 'magisterium' is now applied specifically to the office of teaching in the Church, what is called the 'munus docendi', the teaching authority of the pastors of the Church. And the word magisterium, although part of the classical Latin, enters officially recently in the teaching of the Church : the first entry we find in 'Commissum divinitas' Gregory XVI, the text of 1835.

It says that teaching is the teaching authority of the Church founded on sacramental ordering. This point is decisive: the munus docendi is inextricably linked to the sacrament of the episcopal order.
The term 'Magisterium of the Church', in the Catholic Church indicates their teaching, with whom believes are preserved and pass on the deposit of faith through the centuries, or the doctrine revealed to the apostles by Jesus.

The Magisterium can be ordinary or extraordinary. The ordinary one is the normal mode with which the Church communicates his teaching: it can be exercised through encyclicals, pastoral letters, other written documents, or through the oral preaching by the Pope and the Bishops.

The extraordinary magisterium, however, consists of a pronouncement of an ecumenical council or one of the Pope 'ex cathedra', that defines a truth of faith of dogmatic nature according to the forms dictated by the dogma of papal infallibility.

Text translation from the relazione sul Magistero della Chiesa (clicca per scaricare pdf)
Author: Prof. Don Mauro Gagliardi
Ordinario di teologia dogmatica presso il Pontificio Ateneo “Regina Apostolorum” di Roma
Relazione del 4 marzo 2008 – Cappella del S. Rosario, largo S. Tommaso d’Aquino - Salerno, Don Mauro Gagliardi

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