This is the versicle chanted in the Roman Rite by the deacon at the end of Mass, after the Post-Communions. It is our formula of the old dismissal (apolysis) still contained in all liturgies. It is undoubtedly one of the most ancient Roman formulæ, as may be seen from its archaic and difficult form. All the three oldest Roman Ordines contain it. "Ordo Rom. I" says: "When the prayer [Post-Communion] is over, that one of the deacons appointed by the archdeacon looks towards the pontiff to receive a sign from him and then says to the people: Ite missa est. They answer: Deo gratias (ed. Atchley, London, 1905, p. 144. See also "Ordo Rom. II", 15; "Ordo Rom. III", 18). The medieval commentators were much exercised to explain the meaning of the strange expression. Durandus (Rationale, IV, 57) suggests several interpretations. It has been thought that a word is omitted: Ite, missa est finita; or est is taken absolutely, as meaning "exists", is now an accomplished fact". The real explanation seems to lie rather in interpreting correctly the word missa. Before it became the technical name of the holy Liturgy in the Roman Rite, it meant simply "dismissal". The form missa for missio is like that of collecta (for collectio), ascensa (ascensio), etc. So Ite missa est should be translated "Go it is the dismissal."—Catholic Encyclopedia.
Go forth, the Mass is ended.
Go announce the Gospel of the Lord
Go in peace glorifying God with your life.
Post-Synodal Apostolic Exhortation Sacramentum Caritatis of the Holy Father Benedict XVI to the bishops, clergy, consecrated persons and lay faithful on the Eucharist as the source and summit of the Church’s life and mission (2007).
The Eucharist and mission
84. In my homily at the eucharistic celebration solemnly inaugurating my Petrine ministry, I said that "there is nothing more beautiful than to be surprised by the Gospel, by the encounter with Christ. There is nothing more beautiful than to know him and to speak to others of our friendship with him." (233) These words are all the more significant if we think of the mystery of the Eucharist. The love that we celebrate in the sacrament is not something we can keep to ourselves. By its very nature it demands to be shared with all. What the world needs is God's love; it needs to encounter Christ and to believe in him. The Eucharist is thus the source and summit not only of the Church's life, but also of her mission: "an authentically eucharistic Church is a missionary Church." We too must be able to tell our brothers and sisters with conviction: "That which we have seen and heard we proclaim also to you, so that you may have fellowship with us" (1 Jn 1:3). Truly, nothing is more beautiful than to know Christ and to make him known to others. The institution of the Eucharist, for that matter, anticipates the very heart of Jesus' mission: he is the one sent by the Father for the redemption of the world (cf. Jn 3:16-17; Rom 8:32). At the Last Supper, Jesus entrusts to his disciples the sacrament which makes present his self-sacrifice for the salvation of us all, in obedience to the Father's will. We cannot approach the eucharistic table without being drawn into the mission which, beginning in the very heart of God, is meant to reach all people. Missionary outreach is thus an essential part of the eucharistic form of the Christian life.
Pope St. John Paul II—Redemptoris Missio (Dec. 7, 1990)On the permanent validity of the Church's missionary mandate
One of the central purposes of mission is to bring people together in hearing the Gospel, in fraternal communion, in prayer and in the Eucharist. To live in "fraternal communion" (koinonia) means to be "of one heart and soul" (Acts 4:32), establishing fellowship from every point of view: human, spiritual and material. Indeed, a true Christian community is also committed to distributing earthly goods, so that no one is in want, and all can receive such goods "as they need" (cf. Acts 2:45; 4:35). The first communities, made up of "glad and generous hearts" (Acts 2:46), were open and missionary: they enjoyed "favor with all the people" (Acts 2:47). Even before activity, mission means witness and a way of life that shines out to others.
27. The Acts of the Apostles indicates that the mission which was directed first to Israel and then to the Gentiles develops on many levels. First and foremost, there is the group of the Twelve which as a single body, led by Peter, proclaims the Good News. Then there is the community of believers, which in its way of life and its activity bears witness to the Lord and converts the Gentiles (cf. Acts 2:46-47). Then there are the special envoys sent out to proclaim the Gospel. Thus the Christian community at Antioch sends its members forth on mission; having fasted, prayed and celebrated the Eucharist, the community recognizes that the Spirit has chosen Paul and Barnabas to be "sent forth" (cf. Acts 13:1-4). In its origins, then, mission is seen as a community commitment, a responsibility of the local church, which needs "missionaries" in order to push forward toward new frontiers. Side by side with those who had been sent forth, there were also others, who bore spontaneous witness to the newness which had transformed their lives, and who subsequently provided a link between the emerging communities and the Apostolic Church.
Every community, if it is to be Christian, must be founded on Christ and live in him, as it listens to the word of God, focuses its prayer on the Eucharist, lives in a communion marked by oneness of heart and soul, and shares according to the needs of its members (cf. Acts 2:42-47). As Pope Paul VI recalled, every community must live in union with the particular and the universal Church, in heartfelt communion with the Church's pastors and the Magisterium, with a commitment to missionary outreach and without yielding to isolationism or ideological exploitation.
67. As co-workers of the bishops, priests are called by virtue of the sacrament of Orders to share in concern for the Church's mission: "The spiritual gift that priests have received in ordination prepares them, not for any narrow and limited mission, but for the most universal and all embracing mission of salvation 'to the end of the earth.' For every priestly ministry shares in the universal scope of the mission that Christ entrusted to his apostles." For this reason, the formation of candidates to the priesthood must aim at giving them "the true Catholic spirit whereby they will learn to transcend the bounds of their own diocese, country or rite, and come to the aid of the whole Church, in readiness to preach the Gospel anywhere." All priests must have the mind and the heart of missionaries - open to the needs of the Church and the world, with concern for those farthest away, and especially for the non-Christian groups in their own area. They should have at heart, in their prayers and particularly at the Eucharistic Sacrifice, the concern of the whole Church for all of humanity.
71. Recent popes have stressed the importance of the role of the laity in missionary activity. In the Exhortation Christifideles Laici, I spoke explicitly of the Church's "permanent mission of bringing the Gospel to the multitudes - the millions and millions of men and women - who as yet do not know Christ the Redeemer of humanity," and of the responsibility of the lay faithful in this regard. The mission ad gentes is incumbent upon the entire People of God. Whereas the foundation of a new church requires the Eucharist and hence the priestly ministry, missionary activity, which is carried out in a wide variety of ways, is the task of all the Christian faithful.
World Mission Day, which seeks to heighten awareness of the missions, as well as to collect funds for them, is an important date in the life of the Church, because it teaches how to give: as an offering made to God, in the Eucharistic celebration and for all the missions of the world.
As Catholic Christians, can we make the goal of the New Evangelization about anything other than bringing people into the Mass, the place where or when Christ brings people into an intimate communion with Him through His word and His Body and Blood?