Public Worship consists of Prayer and Sacrifice. The Sacrifice is the Sacrifice of the Cross offered by priests who share in the priesthood of Jesus Christ and stand in his stead. The Sacrifice is always accompanied by Public Prayer, and the whole service is called the Mass. Besides the Mass, the Liturgy also contains the prayers and ceremonies used in the administration of the seven Sacraments; this part is known as the "Ritual of the Sacraments." Then we have the Divine Office, or the Public Prayer, properly so called. Office means "duty," and it is the duty of the public officials of the Church to offer this prayer daily to God in the Church's name. We must bear in mind that the saying of the Office is a public action, whether performed in a crowded cathedral or in the privacy of a priest's room. In addition to the Ritual of the Sacraments, we have the Ritual of the Sacramentals, containing the various blessings of the Church. Finally, we have prayers and ceremonies for special occasions, such as the Visitation of the Sick, the Burial of the Dead, Processions, and the like.
We have seen that the word Mass is applied to that order of public prayer and sacrifice which is the highest act of Christian worship. Mass is the English form of the Latin word "Missa," which means a dismissal or sending away. As we have already remarked, it was the custom of the early Christians to conceal from the pagans the higher truths of the faith. They preached openly the necessity of faith and penance, the giving of the Holy Ghost, the resurrection of the dead and the last judgment, but the deeper doctrines they called mysteries or divine secrets, and those they communicated only to such as had been initiated into the Church. Thus, in the Epistle of the Hebrews the Apostle rebukes the Jewish converts be cause they needed to be told again the rudiments of the faith when he was desirous of explaining to them the secret teaching concerning the Christian priesthood:
"Of whom [Our High Priest Christ Jesus] we have much to say and hard to be intelligibly uttered; because ye are become weak to hear. For, whereas by reason of the time ye ought to be teachers, ye have need to be taught again the first elements of the words of God; and ye are become such as have need of milk, but not of solid food. For every one that is a partaker of milk is unskillful in the word of justice; for he is a little child. But solid food is for the perfect, for them who by custom have their senses exercised to the discerning of good and evil. Wherefore let us leave the word of the beginning of Christ and go to the things more perfect, not laying again the foundation of penance from dead works, and of faith toward God, of the doctrine of baptisms and laying on of hands, and of the resurrection of the dead and of eternal judgment." (Hebrews 6)
Now, "the things more perfect" were carefully concealed from the pagans; and when the Christians spoke of them they called them by names which would not disclose their real nature. The Sacrifice, being, of course, the highest and holiest act" of worship, was not celebrated before the heathens. We shall find, too, that it was kept hidden even from those who were preparing for initiation. The latter were called "Catechumens," that is to say, persons learning the Catechism. They were present at the public prayer which preceded the Sacrifice. When, however, that prayer was ended an officer of the Church formally "dismissed" them. Then, at the conclusion of the Sacrifice, the initiated received their "dismissal" also in the same formal manner. Hence, the whole service was spoken of as the "dismissal" or "dismissals" in Latin "Missa," singular, or "Missae," plural. The Christians would know what was meant by the word, but the nature of the service was concealed from the pagans and catechumens.
As many of the Church services ended also in a dismissal of the people, we find that the word Mass or Masses was applied to them. In the sixth century Vespers or Evening Prayer was called Evening Mass; but this use is now obsolete. Later on, as the Mass was the great feature of festival days, we find that the word was used in the sense of festival or celebration. Hence we have Christmas, or Christ's feast, Michaelmas, or the feast of Saint Michael. Again, the word "Kirmess," now used for a Church fair, or, in fact, for any bazaar or festival, is a shortening of the German term "Kirchmesse" or "Churchmas," and originally meant the celebration held on the anniversary of the dedication or consecration of a Church.
In the New Testament the Sacrament is called the "Breaking of Bread," in memory of the fact that at the Last Supper our Lord took the bread, blessed and brake it, and gave it to His disciples. It is also known as the "Lord's Supper," because it was instituted at the Last Supper taken by our Lord with the Apostles.
"They therefore that received (Peter's) word were baptized; and there were added (to the Church) in that day about three thousand souls. And they were persevering in the doctrine of the Apostles and in the communication of the breaking of bread and in prayers." (Acts of the Apostles 2)
"When ye come therefore together into one place it is not now to eat the Lord's Supper, for every one taketh before his own supper to eat. And one indeed is hungry and another is drunk. What, have ye not houses to eat in and to drink in? Or despise ye the Church of God and put them to shame that have not? What shall I say unto you? Do I praise you? In this I praise you not. For I have received of the Lord that which I also delivered unto you, that the Lord Jesus, the same night in which He was betrayed, took bread, and, giving thanks, brake and said: Take ye and eat: this is My body, which shall be delivered for you: do this for the commemoration of Me. In like mpnner also the chalice, after He had supped, saying: This chalice is the New Testament in My blood: this do ye as often as ye shall drink for the commemoration of Me. For as often as ye shall eat this bread and drink the chalice, ye shall shew the death of the Lord until He come. Therefore, whosoever shall eat this bread or drink the chalice of the Lord unworthily, shall be guilty of the body and of the blood of the Lord. But let a man prove himself, and so let him eat of that bread and drink of that chalice: for he that eateth and drinketh unworthily, eateth and drinketh judgment to himself, not discerning the body of the Lord." (1st Epistle to the Corinthians 11)
Among the Easterns, as we have seen before, the Mass is called the Liturgy. It was known also as the Mystery, the Sacrifice and the Offering in various places. All through the West, however, the word Mass became the common name for the Sacrifice, with the curious exception of the Celtic-speaking peoples. In Irish the word Mass is never used; the Sacrifice is always called the "Offering of the Body of Christ," or, briefly, the "Offering."
While there is only one Sacrifice, yet the form of the accompanying Public Prayer is sometimes simpler and sometimes more elaborate. Thus on great feasts we have Mass celebrated with a number of ministers and singing; at other times it is said by only one person, and there is no music. As we have seen, the Roman Liturgy admits of solemn celebrations and private celebrations. Now, it is well to bear in mind the great division into solemn Mass, or High Mass, and not-solemn or Low Mass. High Mass is sung, and the sacrificing priest is attended by various ministers, whose names and functions we shall study hereafter. When the Sacrificing Priest is a High Priest or Bishop this Mass is called Solemn Pontifical Mass, the Latin word "Pontifex," in English "Pontiff," meaning a High Priest. A Mass which is not sung is called a Low Mass. Between High Mass and Low Mass there is a form very common in this country and improperly called a High Mass. It is a Mass sung by a Priest without the attendant ministers. The proper name for it is a "Missa Cantata," or "Chanted Mass." There are many other kinds of Mass, distinguished either by the place in which they are said or the object for which they are offered, but it will be sufficient to" bear in mind now the great distinction between High Mass and Low Mass, the former being the solemn and more elaborate form, the latter being the simpler and more unceremonious method.
- taken from The Mass, by Father Peter Christopher Yorke