1322 The holy Eucharist completes Christian initiation. Those who have been raised to the dignity of the royal priesthood by Baptism and configured more deeply to Christ by Confirmation participate with the whole community in the Lord’s own sacrifice by means of the Eucharist.
1323 “At the Last Supper, on the night he was betrayed, our Savior instituted the Eucharistic sacrifice of his Body and Blood. This he did in order to perpetuate the sacrifice of the cross throughout the ages until he should come again, and so to entrust to his beloved Spouse, the Church, a memorial of his death and resurrection: a sacrament of love, a sign of unity, a bond of charity, a Paschal banquet ‘in which Christ is consumed, the mind is filled with grace, and a pledge of future glory is given to us.'”
1324 The Eucharist is “the source and summit of the Christian life.” “The other sacraments, and indeed all ecclesiastical ministries and works of the apostolate, are bound up with the Eucharist and are oriented toward it. For in the blessed Eucharist is contained the whole spiritual good of the Church, namely Christ himself, our Pasch.”
The Eucharist was, far and away, the strongest magnet in my journey into the Church. This fitting, since, in the Eucharist, Christ is raised up in mercy-giving glory. Christ promised that when he is raised up, he will draw all people to Himself (cf. John 12:32ff.). Once I actually understood the Eucharist – well, as far as the word “understand” can apply to such a sublime Mystery! – once I understood what the Church meant by the Eucharist, I knew, deep in my heart, there was no turning back. The Eucharist came for me the pearl of great price, for which I was willing to lose anything (cf. Mth. 13:44-46): my Protestant assumptions, my Evangelical reputation, my intransigent anti-Catholicism, even the dignity of not panting “unspiritually” for physical bread and wine etc. Once I understood the offer Christ made in the Lat Supper, and therefore continues to make through His Church to this very day – once I grasped this immense invitation, I knew I could only say Yes. To know Christ humbled Himself every Mass into the form of meager bread – just as he humbled himself in history in the form of a slave (cf. Php. 2:5ff.) – to know this offer and to know I loved Him meant nothing else than panting for Him in that Eucharistic feast.
It’s strange to say, but one of the most powerful Eucharistic experiences I ever had was in my former Presbyterian (PCA) church back in Florida. I was an usher that Sunday and held the loaf out to members as they came forward to receive what were meant to be the Holy Gifts. Although Presbyterians, like all Protestants, reject the doctrines of transubstantiation, the propitiatory power of the Mass, and the identity of the Lord’s Presence with the Gifts, I was overcome by the reality of all three of the truths in a little Presbyterian service over two years ago. As the people came forward, I held out the bread for them to tear off a piece and consume.
Mysteriously, the longer I held the bread, the more truly I knew I held Christ Himself. Every time someone tore off a hunk of the bread, my heart winced, knowing, on the one hand, that such was what our sin did to Christ’s body on the Cross – and does to his Body the Church today – and yet, on the other hand, that such brutality is exactly how God deigns to reconcile us to Himself. I shouted within my heart for the people to tear off the life-giving bread, because without it, they were dead in their sins. I knew Christ’s humility and presence then in a way I never did before, and have only felt again in a few moments of Eucharistic adoration.
Christ is the light from the East and the Eucharist is his love in the feast. The Eucharist is the fullness of Christ’s offer to mankind today. Receiving this gift entails mankind be as fully – officially and spiritually – united to His Body as possible. Agreeing to be formally united to the Catholic Church means you agree with its view of the Eucharist and desire to be just as formally and fully united with Christ himself in that gift. The Holy Gifts are not and cannot be mere symbols, or even more robust “consubstantial” realities, since Christ’s offering was and is pure and completed by no lesser thing. Christ was not a ginger bread man offered on the Cross; he was flesh and blood, soul and divinity. His sacrifice in the Mass, therefoire, cannot be a ginger bread offering. It must be the same Christ through and through. The Bread and Wine truly are Christ himself apart from anything else because Christ offered the Father to us – us to the Father – in Himself apart from anything else. All our gifts are gifts we give back to God. If it is to be our greatest gift to God, the Eucharist must therefore be nothing less (or more) than God’s greatest gift to us: Christ’s Body, Blood, Soul and Divinity.
 Incidentally, this passage in John 12 was one of the more significant Scriptures to shake my Calvinism. While Calvinists emphasize the irresistibility and particularity of the Father’s call described in John 6, they rarely ever mention this passage only six chapters later which expands on the Father’s draw: he draws all people synergistically to Himself in Christ, by grace, not merely a monergistically predetermined set of the elect by fiat.
 Of course, since the pastor lacked the sacramental authority to transform the Gifts into the Body, Blood, Soul and Divinity of our Lord, what I experienced was the sacramental truth trying to burst through the veil of unconsecrated bread. I was sensing the Spirit groaning for the fullness of truth in yet thwarted sacramental means.