OFFICE FOR THE LITURGICAL CELEBRATIONS
Introductory Rites Unite Priest and Congregation
At this early stage of the Mass, the rites seem to speak for themselves. We have neither arrived at the Liturgy of the Word, which proclaims the sacred Scriptures, nor have we prepared the altar for the sacrifice of the Mass. However, a sense in which we have done both of these things is in the inner disposition of the priest.
When the Introductory rites occur, various actions, invisible to the congregation, have already taken place. These not only set the scene for the holiest of holies, but also distinguish in a priest's life the manner in which he arrives at his appointment at the altar so that the demands of the world shall not jar against the recollected sacredness the celebration of holy Mass requires.
The priest has made his private preparation, which is outlined in the missal, whether of the ordinary or of the extraordinary form. The distinction between the two forms is highlighted not only because they form the current usage of the Roman rite, but also because they compliment each other in their aims "to impart an ever increasing vigour to the Christian life of the faithful; to adapt more suitably to the needs of our own times those institutions which are subject to change; [and] to foster whatever can promote union among all who believe in Christ."
The "Praeparatio ad Missam" of both forms share in common a prayer of St. Ambrose, a prayer of St. Thomas Aquinas and a prayer of Our Lady. The Formula of Intention reminds the priest that he confects the Body and Blood of Christ for the benefit of the whole Church and for any who have commended themselves to his prayers. Since this formula pertains to both forms, it can be seen that both forms protect the ecclesiological dimension of the Mass. The priest who celebrates even privately does not celebrate Mass for himself alone.
The Institutio Generalis Missalis Romani, No. 93, explains this, and alongside describes the dispositions that shall occupy the celebrating priest: "A priest who possesses within the Church the power of Holy Orders to offer sacrifice in the person of Christ, stands for this reason at the head of the faithful people gathered together […], presides over their prayer, proclaims the message of salvation to them, associates the people with himself in the offering of sacrifice through Christ in the Holy Spirit to God the father, gives his brothers and sisters the bread of eternal life, and partakes of it with them. When he celebrates the Eucharist, therefore, he must serve God and the people with dignity and humility, and by his bearing and by the way he says the divine words he must convey to the faithful the living presence of Christ."
Gestures of readiness
As a consequence, the Introductory rites presuppose that the priest arrives at the altar ready for his sacred duties. At the same time, no less is expected of the People of God present who are to unite themselves with the action of the Church and shun any appearance of individualism or division. "This unity is beautifully apparent from the gestures and postures observed in common by the faithful."
While the extraordinary form poignantly reminds us that the vested priest approaches the altar, having made the necessary reverences, it takes care to illustrate the care with which the priest must make the Sign of the Cross.
The more extensive introductory rites of the extraordinary form are distinguished by Psalm 42 with its famous antiphon "Introibo ad altare Dei ad Deum qui laetificat iuventutem meum" recited between the priest and the server. The Confiteor is prayed twice, once by the celebrant and then by the server who recites the Misereatur after that of the priest. After the second Confiteor, the Misereatur, which has been retained in the ordinary form of the Mass, but which prays for the forgiveness of our sins generically, rather than allowing for the distinction between those of the priest and those of the people, is followed by the Indulgentiam, where the priest makes the Sign of the Cross over the congregation as he prays for the remission of the sins of us all.
Versicles from Psalm 84 follow. Guéranger describes their purpose as follows: "The practice of reciting these Versicles is very ancient. The last gives us the words of David, who, in his 84th Psalm, is praying for the coming of the Messias. In the Mass, before the Consecration, we await the coming of our Lord, as they, who lived before the Incarnation, awaited the promised Messias. By that word mercy, which is here used by the Prophet, we are not to understand the goodness of God; but, we ask of God, that he will vouchsafe to send us him, […] the Saviour, by whom salvation is to come upon us. These few words of the Psalm take us back in spirit, to the season of Advent, when we are unceasingly asking for him who is to come."
The priest says secretly as he ascends to the altar, "Aufer a nobis," praying that God may remove our sins and that our minds may be rightly disposed as we enter the Holy of Holies. Then he kisses the altar and prays through the merits of the saints, particularly through those whose relics are in the altar, that God be indulgent toward his own sins. At high Mass, the priest incenses the crucifix and then the altar and in such a way as to cover every portion of the altar with incense. A diagram in the missal describes the precise way in which this is to be done. This act reminds us that the altar represents Christ.
Dom Guéranger recounts scriptural significance of this usage. "Holy Church has borrowed this ceremony from heaven itself; where St. John witnessed it. In his apocalypse, he saw an Angel, standing, with a golden censer, near the altar, on which was the Lamb, with four-and-twenty elders around him. He describes this Angel to us, as offering to God the prayers of the Saints, which are symbolised by the incense. Thus, our holy Mother the Church, the faithful Bride of Christ, wishes to do as heaven does."
The ordinary form begins by emphasising the presence of the people assembled before mentioning the procession of the priest and ministers to the altar, which is accompanied by the singing of the Introit. The substitution of hymns for the Introit and the Communion Antiphon has effectively implied the loss of these proper texts of the Mass. Though they have been translated into the vernacular alongside other texts, it is rare indeed that one hears these texts sung, particularly in parishes.
Nonetheless, the liturgy begins with song during which the priest may incense the altar. The opening words of the Mass are the same in both of its forms: "In the name of the Father, and of the Son, and of the Holy Spirit." Led by the celebrant, priest and people make the gesture together and bridge the time that has passed between the historical death of Christ on the cross and the sacrifice of Christ on Calvary that is made present on the altar each time the Mass is celebrated. As Father Jeremy Driscoll writes, "Our own bodies will be drawn into the body that hung on the cross, and this sharing in the death of Christ is the revelation of the Trinitarian mystery."
"In the name" suggests that we entrust the celebration into the name of the Trinity. It is by baptism that we are immersed and entrusted into the name of God. As in baptism we are buried and rise with Christ, so in making the Sign of the Cross we actively renew our faith in the Trinitarian name of God. The Sign of the Cross is not only the traditional way with which Catholics begin prayer, but the obvious and strongest way of doing so. The Amen is the solemn assent of those who answer.
The Apostolic Greeting welcomes the people. It is so called because it is inspired by the letters of St Paul. Maybe the priest will use "Dominus Vobiscum." Otherwise he will choose another option. All the same, he does not trivialise the greeting by saying "Good Morning." The greeting is formalized because the priest greets the people in his specifically sacramental role where, "in persona Christi capitis," he is greeting the assembly called together by God. The congregation does not respond "Good Morning Father," but, "and with your spirit." As Driscoll continues; "The people are addressing the 'spirit' of the priest; that is, that deepest interior part of his being where he has been ordained precisely to lead the people in this sacred action."
Recognition of sinfulness
The priest leads the faithful in the Penitential rite as he calls people to recognize their sinfulness and ask for God's mercy. The varieties in the missal are many. The Confiteor, which is said by everyone together, encourages the prayers of each person for the others and calls upon the communion of saints to assist us. Another form is redolent of the versicles that follow the Indulgentiam in the extraordinary form. Both of these are followed by the Misereatur and by the Kyrie whose repetitions indicate persistent pleas for mercy. The other form consists in a series of often seasonal petitions or "tropes" followed by the Invocation, Kyrie or Christe Eleison. On a Sunday, feast or special occasion, the priest then intones the Gloria, the song of the angels, which is taken up by those present or sung by the choir which represents the faithful.
The Opening Prayer brings together the role of the priest in the Introductory rites of the Mass. The invitation, "Let us pray," is followed by brief silence. Silence speaks profoundly to the inner being and while being a natural feature in the extraordinary form needs to be fostered in the ordinary form as a normal and humble response to mystery. This is traditionally referred to as the Collect - the Latin verb "colligere" concerns the bringing together of seemingly disparate parts to form a whole.
The liturgy of the Church, through the mouth of the priest, puts into the hearts of the faithful a prayer that sums up what we should all be praying for. Not only does the Collect encourage us to look beyond the smallness of our own needs and petitions, but to hear the prayer said or sung alone by the priest in the name of the whole Church, and to make it the prayer of each one of us. Then, oriented toward God and dedicated to the worship of the blessed Trinity in the service of the sacred liturgy of the Church, priest and people alike may be more attuned to hear the tender voice that calls us so that "under God's protection [we] may attain to the loftier heights of doctrine and virtue."
 Second Vatican Ecumenical Council, "Sacrosanctum Concilium," No. 1.
 The Preparatio in the Missale Romanum 1962 is more extensive.
 Missale Romanum, Editio Typica Tertia, Typis Vaticanis 2002, 1289-1291.
 Second Vatican Ecumenical Council, "Lumen Gentium," No. 28.
 Institutio Generalis Missalis Romani, No. 93.
 IGMR, No. 95.
 IGMR, No. 96.
 "[...] signat se signo crucis a fronte ad pectus, et clara voce dicit:" Missale Romanum 1962.
 P. Gueranger, "Explanation of the Prayers and Ceremonies of Holy Mass," tr. L.Shepherd, ed. Stanbrook Abbey, Worcestershire 1885, 7.
 A. Fortescue-J.B. O'Connell-A. Reid, "The Ceremonies of the Roman Rite Described," 14th ed, St. Michael's Abbey Press, Farnborough 2003, 142.
 Revelation 8:3-4.
 P. Gueranger, "Explanation of the Prayers and Ceremonies of Holy Mass," 8.
 J. Driscoll, OSB, "What happens at Mass," Gracewing Publishing, Leominster 2005, 21.
 "In the person of Christ the Head"
 J. Driscoll, OSB, "What happens at Mass," 25.
 "Ostende nobis Domine misericordiam tuam…".
 A trope, from the Latin tropus, and sometimes disparagingly referred to as a farsato, was originally a phrase or a verse added as an embellishment or insertion into the Sung Mass of the Middle ages. For example, 'Kyrie Lux et Origo eleison' in Missa I in Tempore Paschali. The Missal of Pius V discontinued them.
 Rule of St. Benedict, chapter 73.