The food of the Jews has some features in common with our spiritual food. They are alike in the fact that each signifies the same thing: for both signify Christ. Thus they are called the same food: “All ate the same spiritual food” (1 Corinthians 10:3). He calls them the same because each is a symbol of spiritual food. But they are different because one [the manna] was only a symbol; while the other [the bread of the Christians] contains that of which it is the symbol, that is Christ himself. Thus we should say that each of these foods can be taken in two ways. First, as a sign only, i.e., so that each is taken as food only, and without understanding what is signified; and taken in this way, they do not take away either physical or spiritual death. Secondly, they may be taken in both ways, i.e., the visible food is taken in such a way that spiritual food is understood and spiritually tasted, in order that it may satisfy spiritually. In this way, those who ate the manna spiritually did not die spiritually. But those who eat the Eucharist spiritually, both live spiritually without sin, and will live physically forever. Thus, our food is greater than their food, because it contains in itself that of which it is the symbol.
This doctrine serves Thomas well when he asks why young children (in the Latin Church) do not receive Communion, for apparently, Christ himself made it necessary for salvation, when he solemnly proclaims: “Unless you eat the flesh of the Son of Man, and drink his blood, you have no life in you” (John 6:53). Thomas overcomes this difficulty with an appeal to the notion of attaining a sacrament by desire. In his Summa theologiae, he notes that, just as the catechumen who dies before the Easter Vigil can be saved through his desire for baptism, so the baptized believer still lacking access to the Eucharist can obtain its spiritual fruit, and this, even by an implicit desire (as in the case of children who have not reached the age of reason). Aquinas unpacks this analogy with receiving baptism by desire. One can eat the Eucharist “spiritually” before eating it sacramentally in two ways: in the Old Covenant, where the faithful Israelite ate the physical manna along with the spiritual food provided therein, and in the New Covenant, by a desire of receiving the sacrament of the Eucharist. In his Commentary on the Gospel of John, Thomas explains: “The person spiritually eats the flesh of Christ and drinks his blood . . . is made a sharer in the unity of the Church, which comes through charity.” Hence, “the sacrament is in reality or desire (in voto),” meaning, the res can be obtained before fruitful sacramental eating.
Hence, desire for the Eucharistic Lord becomes a central theme, theologically and in the practice of piety. By “desire,” Thomas especially means acts of hope and charity directed to Christ. These acts involve the soul’s motion or actualized impulse toward God. Such motion is grounded in the supernatural imprint that the Holy Spirit has left in the heart, more specifically, in the hearts of all believers who abide in sanctifying grace. Aquinas develops this psychology of love in dialogue with Dionysius the Areopagite. Thomas notes that the beloved’s absence induces desire, and impels the believer to seek the joy of the beloved’s presence. Charity enables and produces a holy, selfless desire, while hope imparts a positive kind of eros, the wholesome creaturely longing for divine goodness, which promises to satiate the soul’s God-given natural and supernatural longings. The fulfillment of Eucharistic desire is deeper union with the Incarnate Word:
Thus, in reference to Christ [substantially] contained and signified [by the species of bread and wine], one eats his flesh and drinks his blood in a spiritual way if he is united to him through faith and love, so that one is transformed into him and becomes his member.
The Angelic Doctor also adds a precision to Augustine’s exegesis: sacramental eating should not be seen as superfluous, for this kind of eating (or actually receiving the host, or the host and cup) induces a richer spiritual effect than does spiritual eating alone. In other words, spiritual communion does not replace the Mass, but can grant a powerful though (usually) partial share in the fruits of sacramental reception.
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