Mystical Body. — The doctrine of the Mystical Body constitutes one of the central points, if not indeed the central point, of Christianity. It is sketched in the Old Testament Scriptures, revealed by Jesus in the Gospel, expounded by St. Paul and St. John in their Epistles, and applied by the Holy Fathers to the various sectors of dogma and Christian life. St. Thomas and the other scholastics gave it theological explanation. From the authors of the Berullian school in the 17th century down to the present day, it has been studied, preached, and lived with an ardor never before known.
Outline:
I. Concept of the Mystical Body
II. The doctrine of the Mystical Body in the Gospel
III. The doctrine of St. Paul. —IV. The doctrine of the Holy Fathers
V. The theology of the Mystical Body.I. Concept of the Mystical Body
The encyclical of Pius XII of June 29, 1943 begins: “The Mystical Body of Christ, which is the Church,” that is, it identifies the Mystical Body with the Church of Christ. In a strict sense, it refers to the Church Militant, which lives and struggles on earth. In a broader sense, however, like the word Church itself, it also includes the souls in Purgatory (the Church Suffering) and the blessed in heaven (the Church Triumphant). The assertion that those who are not members of the Church but are somehow spiritually united to Christ are included in the Mystical Body is not without danger, for it would suggest that the Church is not the sole way of salvation for all the redeemed. According to the doctrine of Jesus, there is “one flock” (John 21:15-17), and whoever does not listen to the shepherds of Christ’s flock is declared “a Gentile and a tax collector” (Matt. 18:17). Pius XII explicitly states that “those who are divided among themselves for reasons of faith or governance (heretics and schismatics) cannot live in the unity of such a Body.” There remains, however, the possibility that those who in good faith are outside the Church may belong to it in desire and thus be members of the Mystical Body, participating in this way, as it were from without, in the graces of the Redeemer.The Mystical Body of Christ can therefore be defined as that “supernatural society, at once visible and spiritual, organic and living, founded by Christ in virtue of His Redemption, in which all the faithful, united to Jesus and to one another by manifold bonds of grace, faith, charity, and juridical ties, live as members of the life of the mystery of the Head, Jesus Christ, and are moved by the same Holy Spirit, the soul of the whole Christ, who will attain the fullness of His stature at the end of the ages in the glory of heaven.”
It must be immediately emphasized that the two words “visible and spiritual society” avoid two opposite errors: one that would see in the Mystical Body only the invisible union in Christ of those who believe in Him, though separated by contradictory beliefs; and another that would deny the intimate life of the Church and limit itself to considering only its social organization and external juridical aspect. The Mystical Body, like the Incarnate Word, possesses a deep spiritual life together with an organic and social cohesion.
II. The doctrine of the Mystical Body in the Gospel
This social and spiritual unity of the Mystical Body is already in some way outlined in the Old Testament, where the children of Abraham are united among themselves and with Jahweh, forming one people which, as a mystical spouse, is joined to God by a bond of special predilection (cf. E. Mersch, I, ch. 1). Already in the divine sentence of Eden, the seed of the woman foreshadowed not only the Messiah but Christ with all the redeemed, the Head with the members, the whole Christ.It was, however, for Jesus to make this mystery of vital union between Himself and His faithful clear to us. The Kingdom of God, as described by Jesus in the Synoptics, reveals the unity that binds all its members together; while the various parables that illustrate its nature—the mustard seed, the seed sown in the field, the leaven that leavens the dough—reveal a mysterious life, a hidden energy that pervades that spiritual organism. The most perfect expression of this vital union, however, is found in the allegory of life: “I am the true vine,” says the Lord, “and my Father is the vinedresser. Every branch in me that bears no fruit he takes away, and every branch that does bear fruit he prunes, that it may bear more fruit... Abide in me, and I in you... I am the vine, you are the branches. He who abides in me, and I in him... he it is that bears much fruit, for apart from me you can do nothing” (John 15:1-2, 4-5). In these words lies the substance of the entire doctrine of the Mystical Body. The life of which Jesus speaks is a living organism, of which all the parts, united among themselves, are animated by the same divine sap: a sap that flows from the trunk into the branches, from Christ into the faithful, and makes them bear abundant fruit of virtue.
This our union with Jesus has as its exemplar the union of Jesus Himself with His divine Father. In the so-called priestly prayer, on the eve of His Passion, Jesus, lifting up His eyes to heaven, said: “That they may all be one; even as thou, Father, art in me, and I in thee, that they also may be in us” (John 17:21). Jesus, the Son of God, forming one with the Father (John 10:30), becomes, through His Humanity, the divine bond that unites us to the Father.
The privileged means by which our union with Christ is realized is the bread of life: “I am the bread of life, which came down from heaven. If any one eats of this bread, he will live for ever... My flesh is food indeed, and my blood is drink indeed. He who eats my flesh and drinks my blood abides in me, and I in him” (John 6:51-52, 56-57). The reciprocal indwelling of Jesus in us and of us in Jesus is once again the whole mystery of the spiritual union of the faithful with Christ. The consequence of this union is that Jesus will regard as done to Himself whatever good or evil we do to our neighbor, that is, to His members; thus He will say at the Last Judgment: “I was hungry and you gave me food, I was thirsty and you gave me drink, I was a stranger and you welcomed me, naked and you clothed me, sick and you visited me, in prison and you came to me... As you did it to one of the least of these my brethren, you did it to me” (Matt. 25:35-40). Such is the teaching of the Master.
III. The doctrine of St. Paul. — At the very moment of his conversion, the Lord revealed this mystery to Paul: “Saul, Saul, why do you persecute me?” In the person of the disciples, Saul was striking the Master. “Who are you, Lord?” “I am Jesus whom you are persecuting” (Acts 9:4-5). This initial grace matured in the soul of St. Paul; in his Epistles he delineated the manifold aspects of the mystery of the organism of Christ. The salient points of his doctrine can be grouped under two heads: dogma and morals.
1. The dogma of the Mystical Body: i) The faithful form with Jesus one body: they are its members, Christ the Head. “For just as the body is one and has many members, and all the members of the body, though many, are one body, so it is with Christ... You are the body of Christ and individually members of it” (1 Cor. 12:12, 27). And to the Ephesians: “God has put all things under his feet and has made him the head over all things for the Church, which is his body, the fulness of him who fills all in all” (1:22-23). 2) Incorporation into Jesus Christ is effected in Baptism, in which we die to sin with Christ and rise to new life. To the Romans (6:3-5) the Apostle writes: “Do you not know that all of us who have been baptized into Christ Jesus were baptized into his death? We were buried therefore with him by baptism into death, so that as Christ was raised from the dead by the glory of the Father, we too might walk in newness of life.” 3) Being a member
“Jesus Christ dwells in you, He who raised Jesus from the dead will also give life to your mortal bodies through His Spirit who dwells in you” (Rom 8:9-11). 4) The member of Christ participates in His divine sonship as an adopted son: so he writes to the Galatians (3:26-27): “All you are sons of God, through faith in Christ Jesus. For [this is the reason for such sonship], you who have been baptised into Christ have put on Christ.” And to the Romans (8:14): “All who are moved by the Spirit of God are sons of God.” 5) The principle of unity in the whole Christ is above all the Eucharistic bread: “Because there is one bread, we who are many are one body, for we all partake of the one bread” (1 Cor 10:17).
2. The morality of the mystical body: 1) The Apostle’s fundamental affirmation on this point is that the life of the Christian is the very life of Jesus: “Christus vita vestra” (Col 3:4). It is Jesus who lives in us, who speaks in us, who suffers in us: “With Christ I am crucified. It is no longer I who live, but Christ lives in me” (Gal 2:19). “In me Christ speaks” (2 Cor 13:3). “I complete in my flesh what is lacking in the afflictions of Christ for the sake of His body, which is the Church” (Col 1:24). 2) Hence the necessity of dying to whatever is of sinful nature, to the first Adam, to the old man, in contrast to Jesus, the new Adam, as Paul expresses it repeatedly: “Put to death therefore what is earthly in you, having put off the old nature with its practices and having put on the new” (Col 3:5; 10; cf. 1 Cor 15:45). 3) Renewed in this way, the Christian will manifest all the virtues that follow from the life of Jesus in him: sincerity, which shuns falsehood: “Put away falsehood, let every one speak the truth with his neighbour, for we are members one of another” (Eph 4:25); purity: “Do you not know that your bodies are members of Christ? Shall I therefore take the members of Christ and make them members of a prostitute?” (1 Cor 6:15); above all, fraternal charity: “It has been reported to me... that there is quarreling among you. I appeal to you, that all of you agree and that there be no divisions among you, but that you be united in the same mind and the same judgment” (1 Cor 1:10-11).
IV. THE DOCTRINE OF THE HOLY FATHERS
The doctrine on this mystery is developed by the Fathers, the Doctors of the Church, and the great theologians. Irenaeus and Cyprian, Athanasius and Hilary, Gregory Nazianzen and Cyril of Jerusalem, John Chrysostom and Augustine treat at length of the mystery of our union with Christ in one single Body. In the Sacrament of the Altar St John Chrysostom sees to such an extent the cause of our unity in Christ that the very word “body” in him is to be understood sometimes as the physical body of Christ, sometimes as the mystical body, the one being the principle of the other. “And why speak further of communion? We are that body itself. What indeed is the bread? The body of Christ. What do the communicants become? The body of Christ; no longer many bodies, but one body” (In I Cor. hom., 24; PG 61, 200). St Augustine everywhere appeals to the dogma of the mystical unity of the faithful in Christ. In it he finds the sole reason for the immense love with which the Eternal Father loves us all: “God cannot but love the members of His Son, He who loves the Son. Nor has He any reason to love His members, save because He loves Himself” (In Io. tr., 100, 5; PL 35, 123). But here one can only hint at the inexhaustible wealth that the Holy Fathers offer us on this doctrine (cf. E. Mersch, the whole of vol. I and part of vol. II).V. THE THEOLOGY OF THE MYSTICAL BODY
Once the mystery of the mystical body, of the *totus Christus*, as St Augustine often calls it (cf., e.g.: In Ps., 90, Sermo 2; PL 37, 1159), has been acknowledged, it is necessary to explain adequately the sublime affirmations of St Paul and St Augustine: “You are the body of Christ” (1 Cor 12:27); “All men in Christ are one single man” (In Ps. 29, 29; Enarr. 2a: PL 36, 219): one single man, one unique Christ. So as not to fall into a kind of pantheism or panchristism, in the error of those reproved by Pius XII, who “make the divine Saviour and the members of the Church coalesce and fuse into one single physical person” (cited encyclical), it is necessary to determine the nature of this union of us all in Christ. Every union is either purely moral, like that of the members of one family, or it is physical and ontological.1. The constituent elements of the mystical body
a) The Head: “He (Christ), says St Paul, is the Head of the body of the Church” (Col 1:18). The Incarnation placed Christ at the head of humanity; the Son of God made man necessarily became “the firstborn of all creation” (Col 1:15), “the recapitulation of all things in heaven and on earth” (Eph 1:10), “the mediator between God and men” (1 Tim 2:5). The eternal Word, “in whom was life” (Jn 1:4), assumed our nature in the unity of His divine Person and filled it with that grace, a sharing in the divine life, which He then wished to pour out upon all the descendants of Adam the sinner. This function of Head of the mystical body, which belongs to the Incarnate Word, implies, according to St Thomas (Sum. Theol., 3, q. 8, a. 1) and according to the encyclical *Mystici Corporis*, a threefold pre-eminence over the members: 1) pre-eminence of order or dignity: “By His proximity to God, the grace of Christ is higher and prior (to that of all others)” (Sum. Theol., loc. cit.); 2) pre-eminence of perfection: in the manner of the head which, in the human body, contains all the external and internal senses, Christ possesses in His Humanity the fullness of all graces. “The virtues, the gifts, the charisms that are in the Christian society — says Pius XII (loc. cit.) — all shine forth in the most perfect manner in His Head, Christ: ‘In Him all the fullness of God was pleased to dwell’ (Col 1:19)”; 3) above all, pre-eminence of influence. As the head moves and governs the whole body, so Jesus Christ exercises upon His Church a continuous directive and vivifying action. According to Pius XII, this influence is exercised by Jesus Christ in two ways: first, inasmuch as He moves His Body by way of government, directing the members of the Church to the sublime end of eternal life, both directly through the hidden means of His interior inspirations and through the hierarchy which He has instituted (the Roman Pontiff, His Vicar on earth, and the bishops in their several dioceses); secondly, inasmuch as He moves His Body spiritually by way of vital influence, diffusing in every cell of it manifold graces, light and virtues (cited encyclical).b) The Members. The members of the Mystical Body are: 1) first of all those who were incorporated into Him here on earth through Baptism and have not been separated from Him by heresy, schism, excommunication, or by dying in mortal sin. Sinners are not excluded from the Mystical Body, even though they lack its spiritual life; they still adhere to Christ and the Church through the faith they profess, and through various influences from the divine Head, they are recalled to communion in life. 2) The souls in Purgatory, who, having left this life in the peace of Christ, remain forever united to Him, though they must still be purified before enjoying the beatific union. 3) Finally, in a perfect manner, the blessed in heaven, to whom Christ communicates the fullness of His life in glory; the Angels are not excluded, for though they do not resemble Jesus in nature, they resemble Him in grace and receive manifold influences from Him. Yet among the members of the Mystical Body, the Blessed Virgin Mary holds a preeminent place. She is the Mother of the Head according to the flesh and has become, “according to the spirit, the Mother of the members,” as St. Augustine already said (De Virginitate, ch. 6: PL 40, 399) and as St. Louis de Montfort insists (v. Traité de la vraie dévotion à la Sainte Vierge, n. 32). This doctrine was approved by Pius X in the encyclical Ad diem illum (1904): “In the most chaste womb of the Virgin, where Jesus took mortal flesh, there He united to Himself a spiritual body, formed of all who were to believe in Him; and it can be said that, by bearing Jesus in her womb, Mary bore also all those whose life was contained in the life of the Savior.” As a mediator of grace in the closest dependence on Jesus the Redeemer, Mary, through her efficacious intercession, transmits to all that divine life which has its original source in the Incarnate Word.
c) The Soul of the Mystical Body. Like every human or animal being, the Mystical Body has a first principle of life and unity in the diversity of its members, which is called the soul. In the whole Christ, this principle is none other than the Holy Spirit Himself, repeatedly called in Scripture “the Spirit of Jesus” or “the Spirit of the Son” (Acts 16:7; Gal. 4:6). He is therefore, as Pius XII teaches, “this divine principle of life and virtue given by Christ, inasmuch as He constitutes the very source of every created gift and grace... It is the Spirit of Christ who has made us children of God and who places in our hearts that filial sense of love with which we cry: Abba! Father! Our Father!” (Rom. 8:14-17). He is also that principle of unity which, from the various members animated by His breath, forms a harmoniously ordered whole. “To this Spirit of Christ, as to an invisible principle, must be attributed the union of all the parts of the Body with one another and with their exalted Head, since He dwells entirely in the Head, entirely in the Body, and entirely in each of the members” (cited encyclical).
2. The Nature of the Unity Proper to the Mystical Body. “Father, may they all be one in Us” (Jn. 17:21). Thus did Jesus pray on Holy Thursday after the Eucharistic banquet. Certainly, as Pius XII reminds us, this unity does not result from a hypostatic, i.e., personal, union that would make us, with Christ, one single physical person, as occurs in the Incarnate Word. Nor does it imply a substantial union, such as exists in us between body and soul to compose one single nature and substance. Our union with Christ in the Mystical Body must be understood in the accidental order of grace, which, encompassing diverse realities—physical, moral, and juridical—has as its purpose and effect the communication to all the faithful of one and the same divine life, infused by Christ into all in participation in His life of grace, and ultimately in dependence upon His divine sonship.
At the root, or rather at the center, of this mystical union stands the vivifying influence of Christ and His Divine Spirit. This influence, which manifests itself in many ways, is effected above all through the Sacraments, among which Baptism holds a preeminent place, by which we are incorporated into Christ, and the Eucharist, the Sacrament proper to the Mystical Body, which is the ultimate effect (the res tantum) of the Eucharist (Summa Theologiae, III, q. 73, a. 1, obj. 2), as taught by St. Thomas Aquinas and his master St. Albert the Great (v. the cited work in the bibliography by A. Piolanti). From this efficacious influence of the Head upon the members results a likeness of life and grace, a conformity of virtue and holiness, of which Jesus is for all the redeemed the exemplary cause. To the intimate union thus established between us and Christ by the efficient causality of a physical and ontological order are added other bonds of a moral and juridical nature. The closest moral union is that generated “by those three theological virtues with which we are united to God (and to all our brethren) in the most intimate manner” (encyclical Mystici Corporis): the union of minds in adherence to the common revealed truth; the union of wills in the soul toward the attainment of the one Supreme Good; the union of hearts in the ardent love that binds us to Jesus and to one another. There is also a juridical and social union, constituted by those bonds which, in the visible Body of Christ, link the members of the ecclesiastical society through mutual obligations and rights, making us first of all subjects of Christ the Redeemer, since by His Incarnation and Passion He has acquired an incontestable right over us all. Finally, all these converging principles of unity culminate in the common end of the eternal kingdom, to which we are predestined by the decree of the heavenly Father, to the glory of His Only-Begotten, who will finally be “all in all” (Col. 3:11).
In summary, there are seven principles of unity in the Mystical Body: 1) the vital influence of the Head; 2) the proper action of the Sacraments, and especially of the Eucharist; 3) the Holy Spirit as the soul of the Mystical Body; 4) exemplary causality; 5) moral union; 6) juridical bonds; 7) the influence of the final cause. We shall, however, focus on what we have called the fundamental principle of the unity of the Mystical Body: the vivifying influence of Christ the Head.
The Mystical Body of Christ reveals itself first as a communion of supernatural life, which has its origin in Jesus. The Humanity of Christ, hypostatically united to the Word of God, receives within itself a power that enables Him to infuse in us the life of grace. This life of grace is a participation in the divine nature: “We are made partakers of the divine nature” (2 Pet. 1:4); “He gave them power to become children of God” (Jn. 1:12). Divine sonship and communion in the divine nature are gifts that surpass every human concept or desire and every capacity of a created cause. To the question of whether Jesus, as man, can sanctify us and communicate grace, it must be answered that to sanctify means to deify; now, as St. Thomas says, deification pertains only to Him who possesses divinity in His own right, that is, to God alone (Summa Theologiae, I-II, q. 112, a. 1). Therefore, such an influence cannot pertain to the humanity of Jesus. Yet the Angelic Doctor adds: the influence of divine life or grace can be attributed only to God as the principal cause; the humanity of Christ, however, can become an instrumental cause (ibid., ad 1). Just as the Sacraments are permeated by the power of God, which elevates them to become true operative causes of grace, so much the more the human nature of Jesus is made the vehicle of the sanctifying action of the Word, as St. Thomas says: “The humanity of Christ causes grace by virtue of the Divinity united to it” (ibid., loc. cit. and passim). This is what St. Cyril of Alexandria already taught: “The flesh [of Christ]... can give life, though of itself flesh profits nothing. Since it is united to the life-giving Word, it is made wholly life-giving, raised to the power of the Word” (In Io. 4: PG 73, 60). The humanity of Jesus is like the fundamental Sacrament of grace, of which the seven Sacraments are an extension. All communicate to us the deifying influence of the humanity of Jesus.
That influence, however, comes to us in a special way through the Sacrament of the Altar, since it contains not only the operative power of Christ, but Christ Himself. It is pre-eminently the Sacrament of union and incorporation into Christ. Even Baptism, as St Thomas teaches, does not make us members of Christ except by reason of a vow or desire for the Eucharist, through which it transmits the proper influence and effect (Summa Theol., 3a, q. 73, a. 3; q. 79, a. 1, ad 1 [V. COMUNIONE EUCARISTICA]). In that contact with the life-giving flesh of Christ through Communion, man is transformed, body and soul, and made like to Jesus: thus Cardinal Mendoza: “We, united to Christ in body and soul, put on the qualities of His body” (De naturali cum Christo unitate, p. 209). And further explaining the manner of this transformation, the same author adds: “Since Christ is truly present in the Sacrament of the Eucharist by His substance, and through the Sacrament in man Himself, a power that flows from the very substance of Christ permeates the whole man and every part of him” (op. cit., p. 218).
But our vision of this mystery is further enlarged by a fundamental truth: the sanctifying power of Christ’s humanity extends to every one of His actions, even the least. This is the teaching of St Thomas, who, speaking of the Passion of Jesus, enunciates this principle: “All the actions and sufferings of Christ operate instrumentally, by the power of the Divinity, for human salvation” (Summa Theol., 3a, qq. 48 and 6). This principle explains how all the mysteries of Christ are sources of grace. To unite ourselves to these mysteries (and every action of the God-Man is a mystery), whether in the celebration of the liturgy, in meditating the Holy Rosary, or in any other way, day by day and at every moment, is truly to appropriate the treasures of grace enclosed in them. Each mystery, moreover, each action of the Incarnate Word, has its own grace, as was excellently explained in the 17th century by the “French” school of spirituality, following Cardinal de Bérulle: the humility of Christ is imprinted in us when we unite ourselves to it in faith; His purity makes us pure, His meekness makes us meek, His patience and strength make us patient and strong, with that divine patience with which He faced His Passion. This true spiritual communion with the life, death, and resurrection of Jesus causes Jesus to live in us and we in Him, fulfilling the Apostle’s word: “I live, now not I, but Christ liveth in me” (Gal. 2:19). Pius XII also says this in the encyclical Mediator Dei (part 3) on the Liturgy: “By recalling these mysteries of Jesus Christ, the sacred Liturgy aims to make all believers share in them, so that the divine Head of the mystical body may live in its members in the fullness of His holiness.” Here we perceive the spiritual richness of this dogma of the mystical body, which harmonizes both dogma and morals, a dogma thus understood in its practical repercussions already constitutes a morality, the principle and source of all Christian life, from the laborious asceticism of beginners to the loftiest peaks of mystical life, even to perfect union with God through Christ the Mediator.