1. Questions B and C treated the first two reasons the Council of Trent gives for Jesus’ institution of the Eucharist. Trent next says that worthy participation in the Eucharist protects us from mortal sin and overcomes venial sin. Vatican II puts this affirmatively by saying the Eucharist fills the mind with grace (see SC 47).
2. The point made in question B suggests how this is so. To participate in the Eucharist means that, having been united by faith and baptism with Jesus, one offers his sacrifice with him and so offers oneself as a gift to the Father. Thus, one way the Eucharist transforms Christian moral life is by demanding that one live faithfully and avoid mortal sin or repent promptly if one should fall into grave sin.
Thus St. Paul teaches: “As often as you eat this bread and drink the cup, you proclaim the Lord’s death until he comes” (1 Cor 11.26). It follows that only those who have made the baptismal commitment of faith and are faithful to it may share fully in the Eucharist by receiving Holy Communion. Hence, Paul adds immediately: “Whoever, therefore, eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of profaning the body and blood of the Lord. Let a man examine himself, and so eat of the bread and drink of the cup” (1 Cor 11.27–28). This teaching warrants special attention when the sacrament of penance has fallen into widespread disuse, yet few who attend Mass hesitate to receive Communion.
3. From ordinary human experience, moreover, we know that the more we act lovingly toward anyone, the more we love that person. Giving gifts is an act of love, and we care most about those, such as our children, to whom we give the most. Small children for their part love in a certain way—they are affectionate—but their love for their parents matures as they grow up and do things for them. Any beneficent act presupposes love, but beneficence also nourishes and matures love. In doing good, we become involved in the one to whom we do it. Where one’s treasure is, there one’s heart is: One finds the good one has done in the person to whom one has done it, now another’s but still one’s own.
4. God similarly loves us so much because everything good in us comes from him; he hardly wishes ill to what is entirely his (see Wis 11.24–26).
5. This can be applied to the Eucharist. In the Eucharist, we first bring forward bread and wine, goods which God supplies from the bounty of nature and by the work of human hands. We offer these, blessing God in thanks. The priest prays quietly: “Lord God, we ask you to receive us and be pleased with the sacrifice we offer you with humble and contrite hearts.” The gifts represent our very selves, created by God and shaped by our freedom in goodness due to God’s grace. We ask God to receive us and be pleased with our self-offering.12
6. Far surpassing the initial offering of the gifts is the offering, to which it leads, of the sacrifice of Jesus. This is done by the priest who acts in Jesus’ person and by all the faithful who offer him through and with the priest, while at the same time they offer themselves united and transformed in Jesus (see SC 48).
Vatican II makes it clear that priests must teach the faithful “to offer to God the Father the divine Victim in the sacrifice of the Mass, and with it to make an offering of their own life” (PO 5; translation supplied). The requirement and power to make this offering come from the Eucharist itself: “The other sacraments, as well as every ministry of the Church and every work of the apostolate, are linked with the holy Eucharist and are directed toward it. For the most blessed Eucharist contains the Church’s entire spiritual wealth, that is, Christ himself, our Passover and living bread. Through his very flesh, made vital and vitalizing by the Holy Spirit, he offers life to men. They are thereby invited and led to offer themselves, their labors, and all created things together with him” (PO 5). Jesus’ gift of himself to us calls forth our gift of ourselves with him to the Father. Conscious that God gives us so much, we wish to give him something in return.
Vatican II also clearly teaches that all acts fitting to a Christian become spiritual sacrifices pleasing to God (LG 10). The priestly commission of the faithful at large equips them to “. . . produce in themselves ever more abundant fruits of the Spirit. For all their works, prayers, and apostolic endeavors, their ordinary married and family life, their daily labor, their mental and physical relaxation, if carried out in the Spirit, and even the hardships of life, if patiently borne—all of these become spiritual sacrifices acceptable to God through Jesus Christ (cf. 1 Pt 2.5). During the celebration of the Eucharist, these sacrifices are most fittingly offered to the Father along with the Lord’s body. Thus, as worshipers whose every deed is holy, the laity consecrate the world itself to God” (LG 34; translation amended). Through the Eucharist, everything fitting in one’s life becomes a gift to God.
7. Thus, by a sort of virtuous circle, one loves God more as one gives him more, and, loving him more, one wishes to give him still more. In this way the Eucharist fills the mind with grace, overcomes venial sin, and keeps us from mortal sin (see S.t., 3, q. 79, aa. 1, 4, 6).
8. There are many reasons for leading a good Christian life: To prepare the material of the heavenly kingdom (see GS 38), to be united more closely with the obedience of Jesus, to carry his redemptive love to others, to perfect our very selves in his love. All these are gathered up in the supreme consideration: the virtuous circle of love. God has given us everything, and we must thank him with, through, and in Jesus. Thanking him, we love him more, and loving him more, we must live more perfectly to make a better gift.
9. A loving father wants of his children only their own fulfillment in goodness. If they give their father this joy, mutual love and satisfaction grow, and the relationship becomes ever more perfect. The children strive ever harder to please their father; he rewards them with constantly growing approval. By the covenant love celebrated and nurtured in the Eucharist, it is like this between us and God.
In his great encyclical on the liturgy, Mediator Dei, Pius XII strongly emphasizes the theme of offering by all the faithful, which has been developed further by Vatican II. In one respect, Pius’ treatment provides an explicit indication missing from the Council’s documents—namely, that one offers oneself at Communion. In receiving Jesus, one ought to accept his love and offer oneself to his service.13 This requirement of acceptance is expressed in the words: “Go in peace to love and serve the Lord.”
John Paul II also suggests that the Eucharist orders Christian life subsequent to it toward fulfillment in Christ:
To this sacrifice [of Christ upon the cross], which is renewed in a sacramental form on the altar, the offerings of bread and wine, united with the devotion of the faithful, nevertheless bring their unique contribution, since by means of the Consecration by the priest they become the sacred species. This is made clear by the way in which the priest acts during the Eucharistic Prayer, especially at the consecration, and when the celebration of the Holy Sacrifice and participation in it are accompanied by awareness that “the Teacher is here and is calling for you” (Jn 11.28). This call of the Lord to us through his Sacrifice opens our hearts, so that, purified in the mystery of our Redemption, they may be united to him in Eucharistic communion, which confers upon participation at Mass a value that is mature, complete, and binding on human life: “The Church’s intention is that the faithful not only offer the spotless victim but also learn to offer themselves and daily to be drawn into ever more perfect union, through Christ the Mediator, with the Father and with each other, so that at last God may be all in all.”14
This summary indicates all of the aspects of the offering which draws our entire lives into the Eucharist and directs them by it.
12. In the interest of affirming our offering of Jesus with him, which is not in the Offertory, some have denied the reality of offering at the Offertory. But this position is at odds with the liturgical action of bringing forward gifts. See Josef A. Jungmann, S.J., The Early Liturgy: To the Time of Gregory the Great (London: Darton, Longman and Todd, 1959), 117. It is not a case of either/or but of both/and; the offering we make in the Mass is complex and dynamic, not simple and static, as is wrongly assumed.
13. Pius XII, Mediator Dei, 39 AAS (1947) 555–56; The Papal Encyclicals, 233.92–94.
14. John Paul II, Dominicae cenae, sec. 9, 130–34; 8; the internal quotation at the end is from the General Instruction on the Roman Missal, 55 (ed. cit. above, 56).