Baptism and Salvation
"Baptism, which corresponds to this, now saves you, not as a removal of dirt from the body but as an appeal to God for a good conscience, through the resurrection of Jesus Christ."
In question and answer 69, the Heidelberg Catechism takes up baptism, which is the first of two sacraments that Jesus has given to His church. Baptism is the sacrament of initiation that marks its recipients as members of the visible covenant community. Those who have been washed with water in the name of the Father, Son, and Holy Spirit have been set apart from the world and given a distinct calling to be God’s royal priesthood and exclusive, distinctive people (1 Peter 2:9).
Baptism in itself does not prove one’s salvation. The Westminster Larger Catechism (Q&A 167) clarifies the role of baptism, noting that only those who, by faith alone, enter into union with Christ in His death and resurrection have eternal life (Rom. 6:1–14). Not every baptized person does this. At the same time, however, Christian baptism always signifies that the baptized individual is in a special covenant relationship with God that unbaptized people do not share. This relationship has specific responsibilities, chiefly repentance and faith (Mark 8:34–36). Impenitence and unbelief violate this covenant (Col. 1:21–23; Heb. 3:7–19). Baptized people can and do break this covenant, which is a real covenant with real responsibilities. Yet those who break this covenant fully and finally prove that they were never saved to begin with (1 John 2:19). Still, they were covenant members—faithless covenant members but covenant members nonetheless.
For those who do have faith, however, baptism signifies not only their entrance into the visible covenant community but also their entrance into the invisible covenant community. Baptism seals on our consciences the assurance that God has washed us clean by the blood of Christ and placed us in the invisible church, which consists only of those who trust in Jesus. The sacrament helps the faithful see that they are members of more than just the visible church, which is made up of all professing Christians, including those who profess faith falsely. This assurance is provided by the Spirit of God, but it is also conveyed through the washing of water, the Heidelberg Catechism tells us (Q&A 69). As we see and feel the water, we understand more concretely that the blood of Christ removes the filth of sin from our souls just as water washes dirt from our bodies. Baptism is a help to our faith, and it assures all who trust in Jesus alone that they are clean before God’s judgment seat (1 Peter 3:21).
Coram Deo
Throughout history, God has entered into covenants with a visible covenant community, a community identified by its profession of faith. However, not everyone in the visible covenant community possesses faith. Only those who trust in Christ alone are a part of the invisible church, which gets its name from the fact that the true state of others’ hearts is invisible to us but not to God. We must put our faith in Jesus to receive the benefits signified in baptism.