Christian Baptism is in urgent need of being re-visited by the evangelical church. The biblical teaching of the sacraments is that they are 'signs and seals' of God's covenant grace (Romans 4:11). The fore-runner of baptism in the Old Testament was circumcision which God instituted in Genesis Chapter 17. God commanded Abraham: 'And God said to Abraham, “As for you, you shall keep my covenant, you and your offspring after you throughout their generations. This is my covenant, which you shall keep, between me and you and your offspring after you: Every male among you shall be circumcised. You shall be circumcised in the flesh of your foreskins, and it shall be a sign of the covenant between me and you' Genesis 17:9-11. Note the connection between covenant and circumcision.
There is a connection between God's covenant's and God's sign's of the covenant, which in the New Testament are baptism and the Lord's Supper. The shadow of baptism in the Old Testament was circumcision: Whereas circumcision involved the shedding of blood and therefore it pointed forwards to the future shed blood of Christ, baptism points backwards to the shed blood of Christ and Christ's completed atonement. Baptism in the new covenant is to be administered using water and the new covenant name of God, 'the Father, and the Son, and the Holy Spirit'; it is to be applied to adults and the children of believing parents.
As with the sign of the covenant, circumcision in the Old Testament, in the new covenant this sign is also to be applied not only to believers, but also to the children of believers. The exclusion of children in baptism by evangelicals is a mistake. A sincere question remains. In which direction does the sign of baptism point? Baptists would argue that it points to our faith in Jesus and our obedience to Him. However, the signs of the covenant do not point to man but instead to God. This is why the inclusion of children in baptism is such a stumbling block to baptists, because they argue 'how can a child have faith?'.
However, baptism is not connected to the timing of it's ordinance for it's efficacy. The same is true of the Lord's Supper. The waters of baptism speak of the shed blood of Christ and the out-pouring of the Holy Spirit. Titus 3: 5-6 'He saved us, not because of works done by us in righteousness, but according to his own mercy, by the washing of regeneration and renewal of the Holy Spirit, whom he poured out on us richly through Jesus Christ our Saviour, so that being justified by his grace we might become heirs according to the hope of eternal life'.
Baptism declares the priority of grace over faith. We are not saved by faith. We are saved by grace through faith. Ephesians 2:8-9 'For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast'.
It is important that we recover the biblical doctrine of baptism to ensure that God is glorified, and declared to be the alone saviour of sinners, which is by His grace alone.