The Church has wisely ordered the Latin tongue only to be used in the Mass and in the administration of the Sacraments, for several reasons. Latin was the language used by St. Peter when he first said Mass at Rome. It was the language in which that Prince of the Apostles drew up the Liturgy which, together with the knowledge of the Gospel, he or his successors the Popes imparted to the different peoples of Italy, France, Belgium, Spain, Portugal, England, Ireland, Scotland, Germany, Hungary, and Poland. From the time of the Apostles down, Latin has invariably been used at the altar through the western parts of Christendom, though their inhabitants very frequently did not understand the language. The Catholic Church, through an aversion to innovations, carefully continues to celebrate her Liturgy in that same tongue which apostolic men and saints have used for a similar purpose during more than eighteen centuries.
Unchangeable dogmas require an unchangeable language.
Mass is said in Latin because a universal Church requires a universal language. The Catholic Church is the same in every clime, in every nation, and consequently its language must be always and everywhere the same, to secure uniformity in her service. It is a fact well known that the meaning of the words is changed in the course of time by everyday usage. Words which once had a good meaning are now used in a vulgar or ludicrous sense. The Church, enlightened by the Holy Ghost, has chosen a language which is not liable to such changes.