He was a Presbyterian student at a Christian seminary, and he was vehemently anti-Catholic. As he pored over Scripture, however, his prejudices started crumbling, one by one, and he and his wife were eventually received into the Catholic Church. Scott and Kimberly Hahn write about their conversion story, powerfully and unforgettably, in “Rome Sweet Home.”

In this book, which I’ve been re-reading recently, there is a striking section where Scott Hahn—before his conversion—is charged with teaching Protestant students about the Gospel of John.

He hits a big stumbling block when he gets to the passage where Jesus says in no uncertain terms, “Unless you eat the flesh of the Son of Man and drink his blood, you have no life in you.”  As you may recall, many listeners walked away from Jesus at this point because they just couldn’t accept this teaching.

Hahn had been taught that the flesh and blood were merely symbols, so examining this passage really shook him up. He realized that people “would not have been … scandalized by a mere symbol.”

Sometimes we forget that the Catholic belief in the real presence of Christ is not universally embraced by Christians. And this difference in beliefs is vividly shown by the absence of tabernacles in the vast majority of Protestant churches. After all, why have a special, sacred area to house the Holy One of God, the Lord Jesus himself, who said he was “the bread of heaven”—if he isn’t really there?

For me, the respect shown by Catholics for the consecrated bread and wine underscores our belief in the sanctity of the Eucharist. There is an altar lamp near the tabernacle, and when it is lit, this means the Blessed Sacrament is present, which is why we genuflect whenever we cross the center aisle. And if a crumb of consecrated bread falls to the floor, it must be retrieved and consumed. If the host were a symbol, we could pick it up and throw it away.

Symbols certainly have their place but shouldn’t be confused with reality. A wedding ring’s circular shape symbolizes the eternal nature of marriage, but what person yearning to be married would be content with just the ring—and no spouse? And what child, longing for a mother’s hug, would be happy if his mother drew him a heart—the symbol of love—and then turned away?

Many years ago, Southern writer Flannery O’Connor, a faithful Catholic, attended a dinner at the home of another writer, an ex-Catholic, who at one point in the evening launched into a discussion of the Eucharist. O’Connor had been sitting quietly, but when the hostess opined that the Eucharist was merely a symbol and a good one at that, O’Connor could no longer hold her tongue. “Well, if it’s a symbol, to hell with it,” she exclaimed.

Writing to a friend about this event, O’Connor said that remark had been the only defense she’d been capable of at the time. She went on to say that the Eucharist “is the center of existence for me. All the rest of life is expendable.”

Before Scott Hahn was received into the Catholic Church, he attended his first Mass, and when the priest held up the host during the consecration, Hahn was deeply moved.

“I felt as if the last drop of doubt had drained from me. With all of my heart, I whispered, ‘My Lord and my God. That’s really you! And if that’s you then I want full communion with you. I don’t want to hold anything back.’”

There is a poignant moment that occurs after the people walked away from Jesus because of his teaching on his body and blood. Jesus turns to the apostles to ask if they will leave too. Peter speaks for all of us when he says, “Where would we go, Lord? You have the words of eternal life.”

As we receive the Lord at Mass, let’s remember that we are walking in the shadow of a miracle, and in the presence of the eternal God. We should hold nothing back because everything else in life truly is expendable. And in our thanksgiving prayers, we might echo Scott Hahn’s words in our hearts: “My Lord and my God! It’s really you!”