Previously we saw that baptism (1) identifies Christians; (2) signifies and seals the benefits of the covenant of grace; and (3) offers and applies the grace of God. Those are things that baptism does. Our task now is to explain how baptism does those things.
To explain how baptism works, we must first recall what baptism is. Baptism is a sacrament, and a means of salvation (Shorter Catechism 94, 91). A sacrament is, “an holy ordinance instituted by Christ, wherein, by sensible signs, Christ, and the benefits of the new covenant, are represented, sealed, and applied to believers” (Shorter Catechism 92). Said another way, a sacrament is a divinely established ceremony that uses physical things to communicate spiritual benefits (See Hebrews 9:1 ff). Every sacrament has two parts: an outward or physical part, and an inward or spiritual part (Larger Catechism 163). In the sacrament of baptism water is the outward part, and the grace of God is the inward part. The outward part represents or symbolizes the inward part. Think of the Old Testament sacrament of circumcision. The outward part was the cutting away of flesh. The inward part was God’s grace (Genesis 17:11, cf. Romans 4:11). But both the outward part and the inward part were called by the same name. The covenant was circumcision, circumcision was the covenant (Genesis 17:10-11). Both the outward removal of flesh and the inward renewal of the heart were called “circumcision” (Deuteronomy 30:6; Romans 2:29), because circumcision was a single sacrament with two parts, one outward and one inward. So too with baptism. It is a sacrament with two parts each called by the same name. The outward ceremony with water is called “baptism”. The inward influence of the Spirit is also called “baptism” (1Peter 3:21; Matthew 3:11). The washing with water and the work of the Spirit are not two separate sacraments, but rather two parts of the same sacrament (Titus 3:5).
Not only is baptism a sacrament, it is also a means of salvation (1 Corinthians 12:13; Romans 6:3; Galatians 3:27). God uses the outward ceremony to accomplish the inward salvation. In this way baptism is similar to preaching and prayer. In preaching God uses His words to communicate His salvation. In prayer God uses our words to accomplish His will. Baptism, like preaching and prayer, is a means of grace. It differs from preaching and prayer in that it is a ceremony and a sacrament. The Old Testament is filed with many ceremonies and sacraments that God used as means of salvation (e.g. circumcision, sacrifices, offerings, washings, sprinklings, anointings, burnings, and the Passover). The New Testament prescribes only two sacraments, baptism and the Lord’s Supper (Matthew 28:19,20; 1 Corinthians 11:23-25). Though fewer in number, the New Testament sacraments are greater in power (Hebrews 12:22-27). In the New Covenant the Spirit of God does greater work in more people than ever before (Jeremiah 31:33,34).
And now we see how baptism accomplishes the works attributed to it. The power of baptism is not in the water, or even the minister who sprinkles the water. The power of baptism is the Holy Spirit who performs the work and applies the grace promised and purchased by Christ to those who participate by faith in the means that God has appointed (Matthew 3:11; 28:19-20; 1 Corinthians 3:6,7; 12:28; Ephesians 4:11-13; 1 Peter 3:21).
Attribution: By Rick Appleton, originally appeared in Providentially Speaking, a monthly newsletter of Providence Presbyterian Church (PCA)