The word sacrament is a term used to describe the ordinances of baptism and the Lord’s Supper, which the Lord Jesus Christ appointed to be observed in the New Testament church. The word itself was used in first century culture to describe a Roman military oath of allegiance, and as such, it expresses one idea behind these ordinances, which is that Christ binds himself to us, and we bind ourselves to him in them.
Sacraments in the Bible are more than this, however, and there have been many disagreements in history over what they do and how they do it. Sometimes the theological waters get very muddy and there are dangerous rocks below. The Westminster Larger and Shorter Catechisms (LC 161–177; SC 91–97) help to navigate some of these dangerous waters. There we learn that the sacraments are ordinances divinely appointed by Christ. They have two parts: an outward and physical part where truth is presented to our senses, and an inward spiritual part whereby we participate in the reality and commune with Christ by faith.
The relation between these two parts—the sign and the thing signified—is vital to understand. The sign does not become the reality, as Roman Catholicism teaches. Nor are the sacraments merely a sign or memorial as many evangelicals teach. There is rather, as J. G. Vos teaches, a symbolic union between the two so that the sign represents the reality, and an instrumental union by which Christ really uses the outward means to convey his grace, by the Spirit, to the believing recipient. This is key to answering the question in this article, “What do sacraments do?”
They are outward signs to our senses of spiritual realities. The water in baptism symbolizes the washing of regeneration by the Spirit (Tit. 3:5), and the cleansing of our sins in the blood of Christ (Rev. 1:5). The bread and wine in the Lord’s Supper represent the body and blood of Christ. Some argue that Jesus’ statement, “This is my body,” must mean the bread really is his body. But we use this kind of language in a symbolic way all the time. If I showed you a photograph of my family and pointed to each member saying, “This is my wife and this is my eldest son,” you would not think the image really was my family member. In the same way, sacraments represent the realities that are behind them.
They do more than represent—they are a means of grace that God uses to apply the salvation Jesus has purchased to his people. His grace is not conferred automatically but, rightly received, we really do feed by faith on Christ in the Lord’s Supper, and he really does feed us. They are not bare signs.
So, when the Bible tells us that baptism saves (1 Pet. 3:21), we only properly understand this when we rightly grasp how sacraments function as means of grace. The Word of God read and preached is another means of grace, but we do not believe that because Peter says we are “born again” of the Word of God (1 Pet. 1:23), that anyone who therefore hears the Word is automatically born again by it. If this were so, we need only go out to the street and preach, and all who heard would be saved. In the same way, the Bible does not teach that the sacraments automatically convey the grace they signify, yet they are a means of grace which God uses to apply salvation to his people. By them he feeds our souls, strengthens our faith, and enables us to die to sin and live to God.
We refer to the sacraments as signs and seals of God’s covenant. Paul speaks in this way of circumcision in Rom. 4:11. It was a seal of God’s promise that Abraham was righteous through faith. A seal is the official stamp a king or government would place on a letter that would identify his official and legal authentication.
In the same way, baptism seals the promises of God and all that he reveals in his covenant salvation, like our union with Christ and cleansing from sin. The Lord’s Supper certifies all that God has done for his people and gives them in Christ, for example, all Christ did on the cross, all he is doing now from the right hand of the father. All that he will do for you and in you as your Prophet, Priest, and King, to preserve you to everlasting glory. He authenticates all this in the sacraments.
In the Old and New Testaments, God used sacraments to distinguish between the church and the world. So Israel was distinguished from the Philistines—the latter were the “uncircumcised Philistines” (Judg. 14:3; 1 Sam. 17:26). Paul carries this language over into the New Testament to describe how the Gentiles, who were outside the covenant people of God and thus uncircumcised, were being brought into the covenant people of God (Eph. 2:11-13).
Understanding this helps us to see that sacraments mark the boundaries of the visible church. Baptism is the sacrament of initiation into the church and is applied to all those who profess the true religion, together with their children. This obligates the person to live a life of faith in and obedience to Christ.
The Lord’s Supper, which calls for faith to feed on Christ, is a sacrament the Christian repeatedly observes in the church, and one of the things we are doing each time we participate is showing forth the Lord’s death until he comes again (1 Cor. 11:26). We are witnessing in the world and to the world that we are not of this world but trusting in Christ’s salvation and looking for the resurrection of the dead.
There is a tragic irony in this statement because so often the sacraments have been a cause of division in the church. Yet at the heart of their meaning and function is the doctrine of Christian unity.
Paul says, “There is one body, and one Spirit, even as ye are called in one hope of your calling; one Lord, one faith, one baptism, one God and Father of all, who is above all, and through all, and in you all” (Eph 4:4-6). Note the irresistible logic of this. There is one baptism because there is one God, one Church, one Gospel, and one salvation. Baptism is a sign and seal of the unity of all of God’s people. How sad that it has been so misused and contended over. The Lord’s Supper likewise brings all of Christ’s people to one table, where they share one loaf of bread because there is one Christ, and they share one cup of wine because there is one Christ, and all who partake there are declaring they are one in him.
The Lord has given his church great gifts in appointing these ordinances. The whole of our salvation is represented, sealed and applied to us in them. May we be diligent in our use of them by faith, to feed upon him and may we deepen our appreciation of their function in the church.