DOGMATIC CONSTITUTION ON THE CHURCH
Excerpts on the Eucharist
Proclaimed By His Holiness, Pope Paul VI on November 21, 1964
CHAPTER I: THE MYSTERY OF THE CHURCH
As often as the sacrifice of the cross by which "Christ our Pasch is sacrificed" (1 Cor. 5:7) is celebrated on the altar, the work of our redemption is carried out. Likewise, in the sacrament of the Eucharistic bread, the unity of believers, who form one body in Christ (cf. 1 Cor. 10:17), is both expressed and brought about. All men are called to this union with Christ, who is the light of the world, from whom we go forth, through whom we live, and towards whom our whole life is directed.
 Through baptism we are formed in the likeness of Christ: "For in one Spirit we were all baptized into one body" (1 Cor.12:13). In this sacred rite fellowship in Christ's death and resurrection is symbolized and is brought about: "For we were buried with him by means of baptism into death"; and if "we have been united with him in the likeness of his death, we shall be so in the likeness of his resurrection also" (Rom. 6:4-5). Really sharing in the body of the Lord in the breaking of the Eucharistic bread, we are taken up into communion with him and with one another. "Because the bread is one, we, though many, are one body, all of us who partake of the one bread" (1 Cor. 10:17). In this way all of us are made members of his body (cf. 1 Cor. 12:27), "but severally members one of another" (Rom. 12:4). As all the members of the human body, though they are many, form one body, so also are the faithful in Christ (cf. 1 Cor.12:12).
CHAPTER II: THE PEOPLE OF GOD
Though they differ essentially and not only in degree, the common priesthood of the faithful and the ministerial or hierarchical priesthood are none the less ordered one to another; each in its own proper way shares in the one priesthood of Christ.  The ministerial priest, by the sacred power that he has, forms and rules the priestly people; in the person of Christ he effects the Eucharistic sacrifice and offers it to God in the name of all the people. The faithful indeed, by virtue of their royal priesthood, participate in the offering of the Eucharist.  They exercise that priesthood, too, by the reception of the sacraments, prayer and thanksgiving, the witness of a holy life, abnegation and active charity. 11. The sacred nature and organic structure of the priestly community is brought into operation through the sacraments and the exercise of virtues. Incorporated into the Church by Baptism, the faithful are appointed by their baptismal character to Christian religious worship; reborn as sons of God, they must profess before men the faith they have received from God through the Church.  By the sacrament of Confirmation they are more perfectly bound to the Church and are endowed with the special strength of the Holy Spirit. Hence they are, as true witnesses of Christ, more strictly obliged to spread the faith by word and deed.  Taking part in the Eucharistic sacrifice, the source and summit of the Christian life, they offer the divine victim to God and themselves along with it.  And so it is that, both in the offering and in Holy Communion, each in his own way, though not of course indiscriminately, has his own part to play in the liturgical action. Then, strengthened by the body of Christ in the Eucharistic communion, they manifest in a concrete way that unity of the People of God which this holy sacrament aptly signifies and admirably realizes.
15. The Church knows that she is joined in many ways to the baptized who are honored by the name of Christian, but who do not however profess the Catholic faith in its entirety or have not preserved unity or communion under the successor of Peter. For there are many who hold sacred scripture in honor as a rule of faith and of life, who have a sincere religious zeal, who lovingly believe in God the FatherAlmighty and in Christ, the Son of God and the Savior, who are sealed by baptism which unites them to Christ, and who indeed recognize and receive other sacraments in their own Churches or ecclesiastical communities. Many of them possess the episcopate, celebrate the Holy Eucharist and cultivate devotion of the Virgin Mother of God. There is furthermore a sharing in prayer and spiritual benefits; these Christians are indeed in some real way joined to us in the Holy Spirit for, by his gifts and graces, his sanctifying power is also active in them and he has strengthened some of them even to the shedding of their blood.
It is for the priests to complete the building up of the body in the Eucharistic sacrifice, thus fulfilling the words of the prophet, "From the rising of the sun, even to going down, my name is great among the gentiles. And in every place there is a sacrifice, and there is offered to my name a clean offering" (Mal. 1:11). Thus the Church prays and likewise labors so that into the People of God, the Body of the Lord and the Temple of the Holy Spirit, may pass the fullness of the whole world, and that in Christ, the head of all things, all honor and glory may be rendered to the Creator, the Father of the universe.
CHAPTER III: THE CHURCH IS HIERARCHICAL
 The Roman Pontiff and the bishops, by reason of their office and the seriousness of the matter, apply themselves with zeal to the work of inquiring by every suitable means into this revelation and of giving apt expression to its contents; they do not, however, admit any new public revelation as pertaining to the divine deposit of faith. 26. The bishop, invested with the fullness of the sacrament of Orders, is "the steward of the grace of the supreme priesthood," above all in the Eucharist, which he himself offers, or ensures that it is offered, from which the Church ever derives its life and on which it thrives. This Church of Christ is really present in all legitimately organized local groups of the faithful, which, in so far as they are united to their pastors, are also quite appropriately called Churches in the New Testament. For these are in fact, in their own localities, the new people called by God, in the power of the Holy Spirit and as the result of full conviction (cf. 1 Thess. 1:5). In them the faithful are gathered together through the preaching of the Gospel of Christ, and the mystery of the Lord's Supper is celebrated "so that, by means of the flesh and blood of the Lord the whole brotherhood of the Body may be welded together." In each altar community, under the sacred ministry of the bishop, a manifest symbol is to be seen of that charity and "unity of the mystical body, without which there can be no salvation." In these communities, though they may often be small and poor, or existing in the Diaspora, Christ is present through whose power and influence the One, Holy, Catholic and Apostolic Church is constituted. For "the sharing in the body and blood of Christ has no other effect than to accomplish our transformation into that which we receive." Moreover, every legitimate celebration of the Eucharist is regulated by the bishop, to whom is confided the duty of presenting to the divine majesty the cult of the Christian religion and of ordering it in accordance with the Lord's injunctions and the Church's regulations, as further defined for the diocese by his particular decision. Thus the bishops, by praying and toiling for the people, apportion in many different forms and without stint that which flows from the abundance of Christ's holiness. By the ministry of the word they impart to those who believe the strength of God unto salvation (cf. Rom. 1:16), and through the sacraments, the frequent and fruitful distribution of which they regulate by their authority, they sanctify the faithful. They control the conferring of Baptism, through which a sharing in the priesthood of Christ is granted. They are the original ministers of Confirmation; it is they who confer sacred Orders and regulate the discipline of Penance, and who diligently exhort and instruct their flocks to take the part that is theirs, in a spirit of faith and reverence, in the liturgy and above all in the holy sacrifice of the Mass. Finally, by the example of their manner of life they should exercise a powerful influence for good on those over whom they are placed, by abstaining from all wrong doing in their conduct, and, as far as they are able, with the help of the Lord, changing it for the better, so that together with the flock entrusted to them, they may attain to eternal life.
 Whilst not having the supreme degree of the pontifical office, and notwithstanding the fact that they depend on the bishops in the exercise of their own proper power, the priests are for all that associated with them by reason of their sacerdotal dignity; and in virtue of the sacrament of Orders, after the image of Christ, the supreme and eternal priest (Heb. 5:1-10; 7:24; 9:11-28), they are consecrated in order to preach the Gospel and shepherd the faithful as well as to celebrate divine worship as true priests of the New Testament. On the level of their own ministry sharing in the unique office of Christ, the mediator, (1 Tim. 2:5), they announce to all the word of God. However, it is in the Eucharistic cult or in the Eucharistic assembly of the faithful (synaxis) that they exercise in a supreme degree their sacred functions; there, acting in the person of Christ and proclaiming his mystery, they unite the votive offerings of the faithful to the sacrifice of Christ their head, and in the sacrifice of the Mass they make present again and apply, until the coming of the Lord (cf. 1 Cor. 11:26), the unique sacrifice of the New Testament, that namely of Christ offering himself once for all a spotless victim to the Father (cf. Heb. 9:11-28).
29. At a lower level of the hierarchy are to be found deacons, who receive the imposition of hands "not unto the priesthood, but unto the ministry." For, strengthened by sacramental grace they are dedicated to the People of God, in conjunction with the bishop and his body of priests, in the service of the liturgy, of the Gospel and of works of charity. It pertains to the office of a deacon, in so far as it may be assigned to him by the competent authority, to administer Baptism solemnly, to be custodian and distributor of the Eucharist, in the name of the Church, to assist at and to bless marriages, to bring Viaticum to the dying, to read the sacred scripture to the faithful, to instruct and exhort the people, to preside over the worship and the prayer of the faithful, to administer sacramentals, and to officiate at funeral and burial services. Dedicated to works of charity and functions of administration, deacons should recall the admonition of St. Polycarp: "Let them be merciful, and zealous, and let them walk according to the truth of the Lord, who became the servant of all."
CHAPTER IV: THE LAITY
The apostolate of the laity is a sharing in the salvific mission of the Church. Through Baptism and Confirmation all are appointed to this apostolate by the Lord himself. Moreover, by the sacraments, and especially by the Eucharist, that love of God and man which is the soul of the apostolate is communicated and nourished.
CHAPTER V: THE CALL TO HOLINESS
42. 'God is love, and he who abides in love abides in God, and God abides in him' (1 Jn. 4:16). God has poured out his love in our hearts through the Holy Spirit who has been given to us (cf. Rom. 5:5); therefore the first and most necessary gift is charity, by which we love God above all things and our neighbor because of him. But if charity is to grow and fructify in the soul like a good seed, each of the faithful must willingly hear the word of God and carry out his will with deeds, with the help of his grace; he must frequently partake of the sacraments, chiefly the Eucharist, and take part in the liturgy; he must constantly apply himself to prayer, self-denial, active brotherly service and the practice of all virtues. This is because love, as the bond of perfection and fullness of the law (cf. Col. 3:14; Rom. 13:10), governs, gives meaning to, and perfects all the means of sanctification Hence the true disciple of Christ is marked by love both of God and of his neighbor.
CHAPTER VII: THE PILGRIM CHURCH
48. The Church, to which we are all called in Christ Jesus, and in which by the grace of God we acquire holiness, will receive its perfection only in the glory of heaven, when will come the time of the renewal of all things (Acts 3:21). At that time, together with the human race, the universe itself, which is so closely related to man and which attains its destiny through him, will be perfectly reestablished in Christ (cf. Eph. 1:10; Col. 1:20; 2 Pet. 3:10-13). Christ lifted up from the earth, has drawn all men to himself (cf. Jn. 12:32). Rising from the dead (cf. Rom. 6:9) he sent his life-giving Spirit upon his disciples and through him set up his Body which is the Church as the universal sacrament of salvation. Sitting at the right hand of the Father he is continually active in the world in order to lead men to the Church and, through it, join them more closely to himself; and, by nourishing them with his own Body and Blood, make them partakers of his glorious life. The promised and hoped for restoration, therefore, has already begun in Christ. It is carried forward in the sending of the Holy Spirit and through him continues in the Church in which, through our faith, we learn the meaning of our earthly life, while we bring to term, with hope of future good, the task allotted to us in the world by the Father, and so work out our salvation (cf. Phil. 2:12). Already the final age of the world is with us (cf. 1 Cor. 10:11) and the renewal of the world is irrevocably under way - it is even now anticipated in a certain real way, for the Church on Earth is endowed already with a sanctity that is real though imperfect.
 It is especially in the sacred liturgy that our union with the heavenly Church is best realized; in the liturgy, through the sacramental signs, the power of the Holy Spirit acts on us, and with community rejoicing we celebrate together the praise of the divine majesty, when all those of every tribe and tongue and people and nation (cf. Apoc. 5:9) - who have been redeemed by the blood of Christ and gathered together into one Church glorify, in one common song of praise, the one and triune God. When, then, we celebrate the Eucharistic sacrifice we are most closely united to the worship of the heavenly Church; when in the fellowship of communion we honor and remember the glorious Mary ever virgin, St. Joseph, the holy apostles and martyrs and all the saints.