Imagine eating the sun—and imagine you could do it without perishing. What would happen? You would receive into your body the source of light and warmth. You would have within you all the light and heat that you could possibly ever need or want. No more heating bills, no more lightbulbs, no more winter trips to warmer climes.
When we receive Jesus in the Most Blessed Sacrament, we receive the source of all supernatural light and warmth, the light of truth, the heat of love, for indeed He is the “sun of Justice.” We receive God Himself, the very Son of God, Who is inseparable from the Father and the Holy Spirit. Saint Ephrem the Syrian wrote:
He called the bread his living body and he filled it with himself and his Spirit . . . He who eats it with faith, eats Fire and Spirit . . . Take and eat this, all of you, and eat with it the Holy Spirit. For it is truly my body and whoever eats it will have eternal life.
That we are not killed instantly by this contact with eternal and infinite Fire is, in its own way, a greater miracle than would be eating the sun without perishing. Our Lord protects us, courteously hiding His blazing glory lest we be overwhelmed, and gently radiating His peace.
It is because we receive divine fire—a fire far more potent in the range and reach of its possible spiritual effects than any physical fire—that the worthy reception of the Eucharist is purifying, illuminating, and unitive. The Holy Eucharist does within and upon the soul that which fire does within and upon combustible matter, burning away contrary dispositions and transforming the matter into itself. But since the spiritual soul is incorruptible, the soul can become fire without perishing, like the miraculous burning bush. It does for the soul what the fire of the sun does for the earth, spreading light, warming bodies, causing growth.
As we learn from the Fathers, Doctors, and mystics of the Church, the Real Presence of Jesus has a proper effect on our soul and our body. It acts principally on the soul, for, again like the sun, Jesus radiates grace to everything that surrounds Him, everything with which He comes into contact, according to His will, “according to the measure of the giving of Christ” (Eph 4:7).
Like the healing of the woman with the flow of blood, the diseased blood of the old Adam cannot be healed by any human medicine, but only by the touch of the new Adam, the physician of souls. The Lord touches first the essence of the soul, increasing in it the grace that makes the soul pleasing to God, an adopted son of the Father, a sister and bride of the Son (soror mea, sponsa mea, as the Song of Songs says), a temple of the Holy Spirit. He touches the powers of the soul, informing them with virtues, strengthening virtuous habits. He stirs these powers into operation—He produces within us acts of faith, hope, charity, and all the virtues. Only in the life to come will we be given to know just how many times it was Jesus who, faced with the listless torpor of our fallen condition, animated our souls into action and prompted us to bear fruits pleasing to God and profitable to us.
Holy Communion influences the body, too. This is very important to see, even if we cannot understand it completely. Wrapped in the long shadow of Descartes, modern Westerners seem afflicted with a tendency to consider “spirituality” the exclusive domain of the spirit—leaving the flesh to fend for itself like an abandoned orphan. This is not what the Lord who created heaven and earth has in mind for us material creatures. By means of the Holy Eucharist, our flesh is made more obedient and docile to the soul, rendered more receptive to the informing power of soul and virtue.
The Lord is sown into the flesh as a seed of immortality: He radiates divine life, divine existence, upon what has merely earthly life and earthly existence. His presence is like a beneficial radiation. We know that ordinary radiation causes deformity of cells. But the radiation of the Son of God is exactly the opposite; it causes a hidden perfection in cells, in all the matter of the body, so that on the last day the flesh will be recognized in the sight of God as flesh marked by and belonging to Christ, as flesh worthy and able to be resurrected in the image of the glorified King. He wants to change the flesh, day by day, into flesh that He will resurrect as if it were His very own.
Those who have eaten the Eucharist have eaten the flesh and drunk the blood of Him who is the Resurrection and the Life. Their own flesh and blood is invisibly stamped with the signature, the seal, of the eternally living flesh and blood of Jesus. To the all-seeing eyes of God the Father, the man or woman fed on the Eucharist looks different from the one who has not been so fed. Not only in his soul, but in his very flesh, he bears the marks of the Lord Jesus (cf. Gal 6:17). As Saint Thomas says, we receive Christus passus, “the Christ who suffered,” who is now glorified. The body that is conformed to the suffering Christ is conformed to His glory, Saint Paul tells us.
An inverse example may illustrate. If you sow a field with salt, as the Romans did the fields of Carthage, the soil’s capacity to bear fruit is destroyed; it cannot produce crops for many generations. But if you sow the field of the human body with the salt of Jesus Christ, this makes the field fertile for all ages, for eternity; the salt of the Spirit preserves the flesh from corruption. And this is something God finds in the body of the communicant, shaped and affected by the presence of the Son received in Holy Communion. God does not “imagine” a difference; there is an ontological difference. As Reginald Garrigou-Lagrange expresses it: “The Eucharist leaves, as it were, seeds of immortality in the body, which is destined to rise again and to receive a reflection of the glory of the soul.”
There is a causal connection between eating the risen Lord and being raised up, between eating His body and being resurrected in body on the last day to a glorious eternity. Those who have not so eaten are indeed raised from the dead, but their resurrection is a punishment, not a reward; it is a resurrection to judgment and everlasting death, not to life and glory. Saint Thomas notes that the flesh of the damned is not perfect like the flesh of Christ, but rather, is kept permanently susceptible to pain, ever dying but never dead. May the Lord in His mercy spare us from such an inglorious resurrection; may He grant us a share in His glorious triumph over sin and death!
In his magnificent encyclical on the Eucharist, Mirae Caritatis, Pope Leo XIII bears witness to this twofold effect of the divine Sacrament, on the soul and on the body:
By this same Sacrament our hope of everlasting blessedness, based on our trust in the divine assistance, is wonderfully strengthened. For the edge of that longing for happiness which is so deeply rooted in the hearts of all men from their birth is whetted even more and more by the experience of the deceitfulness of earthly goods, by the unjust violence of wicked men, and by all those other afflictions to which mind and body are subject.
Now the venerable Sacrament of the Eucharist is both the source and the pledge of blessedness and of glory, and this, not for the soul alone, but for the body also. For it enriches the soul with an abundance of heavenly blessings, and fills it with a sweet joy which far surpasses man’s hope and expectations; it sustains him in adversity, strengthens him in the spiritual combat, preserves him for life everlasting, and as a special provision for the journey accompanies him thither. And in the frail and perishable body that divine Host, which is the immortal Body of Christ, implants a principle of resurrection, a seed of immortality, which one day must germinate. That to this source man’s soul and body will be indebted for both these boons has been the constant teaching of the Church, which has dutifully reaffirmed the affirmation of Christ: “He that eateth my flesh and drinketh my blood hath everlasting life; and I will raise him up at the last day” (Jn 6:55).
St. John Chrysostom similarly bears witness:
Let us not, I beg you, slay ourselves by our irreverence, but with awe and purity draw near to it; and when you see it set before you, say to yourself: “Because of this Body am I no longer earth and ashes, no longer a prisoner, but free: because of this I hope for heaven, and to receive the good things therein, immortal life, the portion of angels, to converse with Christ.”
Here, then, is the question we must ask ourselves: Do we believe that Jesus Christ, the Lord of heaven and earth, is really, truly, substantially present in the Most Holy Eucharist? If so, we can do far more than just follow Him at a distance, like the scared Apostles during the Passion: we can eat the Way, the Truth, and the Life, we can become one with Him and allow His reality to shape our very self.
The Truth we are striving to know and to behold face to face in the beatific vision—that same Truth is our food, we can consume it and be one with it. The Life we long for, the blessed life, the life of heaven: this Life we can take into ourselves. That God should give us Himself is completely beyond our limited understanding, but not at all beyond His unlimited power. The Way we seek to follow, the Gospel way, is not a philosophy but a Person, the Word made Flesh, and this Person gives Himself to us.
Do we believe He is Emmanuel, “God with us,” God dwelling in our midst? Hidden, yes, but also real—indeed, far more real than we are. Let us go to Him, let us run to reality! God is the source of all reality, all goodness, all holiness, all happiness.
Every one who thirsts, come to the waters; and he who has no money, come, buy and eat! Come, buy wine and milk without money and without price. Why do you spend your money for that which is not bread, and your labor for that which does not satisfy? Hearken diligently to me, and eat what is good, and delight yourselves in fatness.
What does our Lord say in the Gospel of John? “This is eternal life, that they know Thee, the only true God, and Jesus Christ whom Thou hast sent” (Jn 17:3). He also says: “I came that they may have life, and have it abundantly” (Jn 10:10). Holy Mass is the Sacrifice of Christ made real again in our midst; it is His self-offering and ours, too, united with His. It brings us the sacrament of His passion, death, and resurrection, and through it—or better, through communion with the Lord Himself—we suffer, die, and rise again.
It may not always feel like the height of one’s interior life or one’s Christian life, but that is beside the point. Our religion does not consist in feelings or even true thoughts, but communion with mysteries; it is about massive realities too big for our comprehension that God thrusts upon us, and we respond to them in the darkness of faith. We have to trust not our changing feelings or our uncertain thoughts but His everlasting Word, which is the only rock we can safely build on. If we build on the rock of the Mass—the integral, authentic Mass, the unfailing garden of saints, handed down to us through the ages in Catholic tradition—our house will be stably founded forever.
Every man is either living from the Eucharist, or longing to live from it, whether he knows it or not. This is because everyone longs for the life of God, to be a god, to be immortal and perfectly happy, and the Eucharist is the food of immortality, of divinization, whereby God comes to us, and we are lifted up into Him. All this takes place in faith, in a certain darkness, but as long as we rely on the invincible and infallible promises of Jesus Christ, truly present in the Blessed Sacrament, the Eucharist becomes for us the great reassurance that we are heading toward heaven as well as the great source of power to reach this goal, which is so far beyond our power.
We must therefore cling heartily and happily to the Eucharistic Lord, and receive Him as often as we can, go before Him in adoration, let our minds and hearts be “eucharisticized” so that our lives will be, more and more, an act of thanksgiving for His mighty work of redemption in us.
 Sermo IV in Hebdomadam Sanctam: CSCO 413/Syr. 182, 55, quoted by St. John Paul II, Encyclical Letter Ecclesia de Eucharistia (April 17, 2003), n. 17.
 See St. Thomas, Summa theologiae, I-II, q. 110.
 Summa theologiae, III, q. 66, art. 9: “The Eucharist is a commemoration of Christ’s death, in so far as the suffering Christ Himself is offered to us as the Paschal banquet.”
 See, inter alia, Rom 8:17.
 Reginald Garrigou-Lagrange, The Three Ages of the Interior Life, trans. Sr. M. Timothea Doyle, O.P. (Rockford, IL: TAN Books, 1989), 2:112.
 Leo XIII, Encyclical Letter Mirae Caritatis (May 28, 1902), n. 9.
 John Chrysostom, In epistulam I ad Corinthos 24.4 (PG 61, 203), quoted in Pope Benedict XVI, Letter on the Occasion of the Sixteenth Centenary of the Death of St. John Chrysostom (August 10, 2007).
 Is 55:1-2.