Biochemistry & Communion: The Bread

Symbols can be very powerful. They define movements and can evoke strong emotional responses, but some symbols are more effective than others. People who design symbols think very carefully about what they might use. When Jesus met with his disciples for the last supper, he chose to give them two symbols which would help define the Christian movement throughout history: the bread and the wine. As it turns out, these have been very effective symbols. But what is it about the bread and the wine which made them such good choices?

In this article, I want to focus on the bread and examine how it relates to the Christian life by examining it at both the human level and at the biochemical level. Before I progress any further, I want to be clear about my intent and purpose. I am not using modern scientific understanding to uncover some hidden or new meaning in Scripture – that is very inappropriate, even heretical. Rather, I am using some scientific knowledge simply to reflect on truths which we already know from scripture, and help connect some dots.

The communion is regarded by all churches as being one of the sacraments – a means of grace – a way in which, in some sense, Christ enters into the church. The sacraments are symbolic of spiritual realities. The communion in particular reminds Christians both about Christ’s sacrifice, and his indwelling presence. Jesus said, “In that day you will know that I am in my Father, and you in me, and I in you.” (John 14:20) So, how can we liken the eating of bread to Christ being both in individual lives and in the church?

Even in the early church, people had an understanding of the importance of bread. Jesus made several references to bread in his teachings. He told us that “man does not live by bread alone…” (Matt 4:4), and referred to himself as the “bread of life” (John 6:35). While it is a common feature of day-to-day living, bread (in whatever form you eat it) is essential for sustaining life. Certainly, a life in Christ and life within the church is much the same in a spiritual sense. So, how does that play out? This is where a little biochemistry can help us think about that.

For the most part, bread is a chief source of carbohydrates in our diet. After we have chewed and swallowed bread, it makes its way through our digestive system which breaks complex carbohydrate molecules down into simple carbohydrates, namely, sugar. From there these sugars pass into the blood stream where they are delivered to the cells of the body for a variety of uses.

A primary use of sugar in the body is for energy. Energy is an elusive concept – it isn’t something we can grab ahold of in any tangible way, but it is the thing we need to do stuff. In the spiritual life of the Christian, power or energy comes through the Spirit of God – nothing that one can grab ahold of or control, but one experiences its effect. The apostle Paul prays for the Ephesians that “[the Father] may strengthen you with power through his Spirit in your inner being.” (Eph 3:16) This is not a worldly power Christians might use to overthrow governments or conquer nations. Rather, the Spirit’s power is to help those in the church to “grasp how wide and long and high and deep is the love of Christ and to know this love that surpasses knowledge – that you may be filled to the measure of all the fullness of God.” (Eph 3:18-19)

There is also power to be found in the message of the Gospel. As Paul writes, “For the word of the cross is folly to those who are perishing, but to us who are being saved it is the power of God.” (1 Cor 12:18) and “[the gospel] is the power of God for salvation to everyone who believes” (Rom 1:16) In regards to the spreading of the gospel, it is also the spirit of God which enables and empowers the teaching and preaching of the gospel. Paul says of his ministry to “make the word of God fully known” that it is accomplished with a power which exists beyond himself: “for this I toil, struggling with all [Christ’s] energy that he powerfully works within me.” (Col 1:24-29)

Another important use of sugars in the body is its incorporation into DNA. All the information needed to make cells function is stored in this remarkable nucleotide polymer. The encoding of this information happens with the un-patterned sequence of four nitrogenous bases. However, in order to make this information functional, it is held in place by a sugar-phosphate back bone. Each cell of the body has a different function because different genes encoded on the DNA are expressed, but regardless of which genes are expressed, they are all held together with the same sugar-phosphate backbone. It is worth noting that not just any sugar will do here. Scientists have tried to construct DNA using a variety of sugars, but the only one which works successfully is the deoxyribose sugar. So, the cells in your body will take the glucose from the bread you ate and synthesize the needed deoxyribose.

In the human body, its functioning depends on the differentiation of cells and the same thing can be said for the functioning of the church “For the body does not consist of one member but of many…a hand…the ear…an eye… there are many parts, yet one body.” (1 Cor 12:14-20). Each person in the church possesses unique personalities, skills, abilities, and spiritual giftedness which makes the church function as a whole. While differences are important, it is also recognized that the diversity in the church hangs together because everyone is bound together in Christ. “There are different kinds of service, but the same Lord. There are different kinds of working, but the same God works all of them in all men.” (1 Cor 12:5-6)

A third use of sugars in the body relevant to this discussion is their role in surface proteins of our cells known as Major Histocompatibility Complexes (MHC). Some of these structures combine both sugars and proteins (glycoproteins) to create little “nametags” used by our immune system to identify “self”. Cells with the correct MHCs are ignored by the white blood cells, but those with incorrect MHCs are marked for destruction. In effect, the bread we eat helps create the identity of cells – it signals that they belong.

In taking the communion believers are declaring their identity is in Christ. One of the most freeing aspects of the Christian faith is that the worldly identities which encumber us with unattainable expectations are exchanged for an unconditional identity in Christ. “But our citizenship is in heaven. And we eagerly await a Savior from there, the Lord Jesus Christ.” (Phil 3:20) I love the fact that people from all over the world with so many differences in nationalities and ethnicities can all collectively find their identity in Christ.

A final function of carbohydrates to consider is their role in the production of antibodies. Antibodies are also glycoproteins which incorporate carbohydrates in the Fc region of these molecules. Antibodies are central in our ability to fight infection in the body serving to mark foreign bodies (antigens) for destruction. The Fc region of an antibody plays a role in what happens to these antigens after the other side of the molecule has attached to the foreign antigen.

Christians also are fighting an internal battle – a battle with sin. Fortunately, it is a battle which will be won because believers are united with Christ. Because of this union with Christ, He is able to take a believer’s sin upon himself and become the propitiation for those sins. Christ helps not only with the sins of the past, but also with the ongoing struggle with sin. “For sin will have no dominion over you, since you are not under law but under grace.” (Rom 6:14) Making use of the power which comes through Christ, the Christian is able to “fight the good fight of faith” (1 Tim 6:11-16) and overcome the temptations that the world throws our way.

To the point then, the bread really is a good symbol for the Christian life and the life of the church. Bread provides energy, so it points to the power all believers have in Christ. Bread provides important cell structure and points to the unity and identity Christians share in Christ. Bread also plays a role in fighting infections, and points to the Christian’s means of dealing with the sin problem. Just a few things to think about the next time you step to the altar to take the communion!