Baptism is one of the rites of the church. We call it a sacrament. The other sacrament is the Lord’s supper.
The Lord Jesus taught the church to baptize, with water. Just before he ascended to heaven, he told the church, “Therefore go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, and teaching them to obey everything I have commanded you” (Matthew 28:19,20).
Water washes. If your body is dirty, you use water to wash yourself clean. The water of baptism is a sign and symbol of the blood of Jesus Christ. Jesus shed his blood on the cross to cleanse people’s souls of sin. As a visible image of what the blood of Christ does for believers, Christ told the church to use a bit of water to baptize people.
Who should be baptized? Those who confess faith in Christ and their children. In Mark 16:15,16, Christ told the church, “Go into all the world and preach the good news to all creation. Whoever believes and is baptized will be saved, but whoever does not believe will be condemned.”
If people coming to faith and receiving baptism have little children, those children, too, are to receive baptism. When God enters into a relationship of love with people by drawing them into his church, then he draws their young children in with them. In the Book of Acts chapter 16 there are a few examples of this.
The Bible teaches that the children of the church belong to the church. They too receive baptism, the sign that they too, together with their parents, belong to Christ and his church.