When the Apostles parted from each other for their mission to announce to all nations the gospel of salvation, two languages chiefly were spoken and understood by the two great civilized divisions of mankind--the Latin language for the most part in the west and the Geek in the east. They preached the faith chiefly in Latin and Greek; their teachings and their institutions were written in those two rich languages, and the Church has preserved these monuments with a religious veneration. This is one reason why her language is for the most part Latin in the west, and Greek in the east. Yet this which, in fact, is a testimony in favor of her antiquity, is made by some a theme of reproach against her.
Providence had already disposed all in advance. Latin and Greek became dead languages, and hence invariable, and wonderfully adapted to formulate (or express with precision) the doctrines of the Church which alters not because she is divine.
An interesting calculation made on the changes that have been made in the living languages, shows, that had the Church adopted the various languages instead of the Latin, she would have been obliged to modify the formula (or essential words) used in the administration of the sacrament of baptism a great many times; otherwise these formulas would not have expressed correctly the idea they should convey. By this we can judge of the many changes which the wording of the creed, and decrees of the early councils and those of the Popes would undergo, were they not recorded in an unalterable (or dead) language.
Protestants have perhaps reason in preferring the use of spoken modern tongues in their authorized books of religion. Living languages, continually changing, are more suited to convey doctrines which are subject to frequent alteration. But the Catholic Church prefers old, unchangeable languages because she is herself unchangeable.
The Church speaks Latin, not only because she is unchangeable, but also because she is Catholic, or universal, and has to address herself to all people in all times.
During the first four centuries of Christianity Latin was the language of the civilized world, and although then a living language, it had that character of universality which the Church requires. When in course of time the world was divided into many nationalities, the Church still preserved her beautiful primitive language, and thus remained unchanged in her speech as in her essence.
Thus the Church speaks Latin because she is apostolic, unchanging, and Catholic.
St. Paul, it is true, in his First Epistle to the Corinthians (chap. xiv.), directed the Christians to use in their assemblies a language understood by all the faithful present; but many Protestants draw from this an objection which does not apply to the present question.
The Apostle confines himself to the preaching, exhorting, and instructing the assembled faithful, all which, he says, must be done in the vernacular or common language of the people. The word "prophecy" includes instructions--speaking on things divine. The Catholic Church follows this apostolic command to the letter. Her bishops, priests, missionaries, and catechists always employ in their teaching a language understood by all. They speak, when needed, in the most obscure and most barbarous dialects, in order that the Word of God preached may reach the understanding of all.
The Catholic Church speaks not only the particular distinctive language of each land and tribe when instructing the people, but has also a special Catholic language, that her pastors, belonging to every nation, may readily communicate with each other, that they may minister together at the altar, and that her laity, of whatever tongue, may not, when in a foreign land, feel strange in the house of God, but feel at home in any Catholic place of worship, in any part of the world.
In this way the church unites in one universal tongue to implore the mercy and sing the praises of God. This beautiful and sublime harmony of nations in one faith, with one voice, in the one fold of the one Shepherd, is worthy of the Church of Christ, and of the unity which is here grand characteristic.
The Mass is a sacrifice offered directly to God, and it is not necessary for the people to follow in the Latin the words of the priest. When the Catholic priest stands at the altar, though there may be persons present from every clime, so soon as he pronounces aloud any part of the service, all understand, and take an intelligent part in his ministration; a fact which reminds one of the preaching of the Apostles on the Day of Pentecost, when all from every nation heard St. Peter, each in his own tongue. (Acts ii. 6.).
The Church speaks Latin, therefore, not only because she is apostolic, unchangeable, and Catholic, but also because she is one.
Change of language in the liturgy would seem to break the link with the past, and raise some suspicion of innovation in what is expressed in the liturgy; while the having retained the same ancient language indicates that the Church which continues to use it is the very same as of old, and that she has not changed in any essential matter, having been so careful as not to change even her language, which, compared with doctrine, is of much less importance.
It is fairly presumed that the Church which possesses the language of antiquity has antiquity on here side; that, being the inheritor of the language, she is also the inheritor of the ancient faith. The fact of her still using the Latin language makes us feel the more sure that the Catholic Church is the one old, unchangeable Church of God.
The Glories of the Catholic Faith: The Catholic Christian Instructed in Defence of His Faith, Volume I. John Duffy Publisher: New York (Section Third By the Very Rev. Joseph Faa Di Bruno), pp. 176-178.
It stands to reason that those "churches" which follow every novel doctrine should remove themselves from the ancient, apostolic, unchanging and universal language of the Church: long live Latin!