The Holy Sacrament of Baptism
Christ our Lord says in the last chapter of Matthew: "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." Matthew 28:19
God Himself instituted Baptism, for our Lord Jesus Christ commanded His church to baptize all nations. The benefits of Baptism include forgiveness of sins, eternal salvation to all who believe this, as the words and promises of God declare.
"Whoever believes and is baptized will be saved, but whoever does not believe will be condemned." Mark 16:16
Those who can receive instruction are to be baptized after they have been instructed in the main articles of the Christian faith.
Little children should be baptized when they are brought to Baptism by those who have authority over them. Jesus especially invites little children to come to Him.
Babies are baptized because they are included in the words "all nations". As sinners, babies need what Baptism offers. Babies also are able to have faith.