Human beings possess immaterial spirits or souls, but we are also physical creatures who access the world through our five senses. Even when it comes to spiritual matters such as receiving the teaching of God’s Word, most of us rely on our sight and hearing. And even those who cannot see are able to read Scripture via touch through the use of a tactile writing system such as Braille.
Given the kindness of our Creator, we find it no surprise that God has chosen to communicate His grace and truth to us through our senses. In the sacraments, we have physical means of grace, things we touch and taste for the sake of growing in Christ and understanding the gospel. Discussions of the sacraments—baptism and the Lord’s Supper—were an integral part of the Reformation, and they were so because the Bible stresses their importance.
To understand the biblical, Reformed doctrine of the sacraments, we must first know what a sacrament is. The English word sacrament comes from Latin. Its root is the same as that for the word meaning “holy” or “consecrate.” Essentially, sacraments are holy mysteries, not in the sense of being unintelligible but in the sense of revealing truth. They are rites used to reveal truth and set God’s people apart from the world.
This notion of sacraments as ordinances that set us apart reflects their function as seals. Romans 4:11 describes the old covenant sacrament of circumcision as a “seal” of righteousness. In the ancient world, letters were often marked with wax on which a seal from a ring or other object was impressed. The seal proved ownership, indicating that the letter came from the person represented by the seal. Similarly, the sacraments are visible marks that God owns us. They show that we have been set apart from the world as His people. This does not mean that everyone who participates in the sacraments has been saved. Some people bear the mark falsely, not having the faith that alone can save us. Nevertheless, to receive the sacraments is to receive the mark of the visible church and to be incorporated into the visible covenant community that is different from the world.
Today’s passage also describes the old covenant sacrament of circumcision as a sign (Rom. 4:11). Signs point beyond themselves to something else, so the sacraments are visible, tangible indicators that direct us to spiritual realities. They outwardly signify internal realities. They show us what God does for His people in the gospel.