Commentaries:
John 3:23, Matthew 3:16, and Acts 8:38 give conclusive proof that the original method of baptism was by immersion. John needed an abundance of water to cover his followers completely. Jesus' example shows that He "came up . . . from the water" because He had been in it. Philip and the Ethiopian eunuch "went down into the water." In addition, "baptize," from the Greek baptizo, means "to immerse," "plunge into" or "put into." Two entirely different words are used in the Greek text to refer to pouring (cheo) or sprinkling (rantizo).
Richard T. Ritenbaugh
Basic Doctrines: Water Baptism
Christ links repentance with the Kingdom of God and believing the gospel. Once one hears the true gospel and believes it, he begins to change the way he thinks. Peter ties repentance with forgiveness of past sins and God's giving of His Spirit. Once the Ethiopian eunuch heard Philip's explanation of the Bible, he changed his thinking (repented) and was baptized. Initial repentance includes recognition, acceptance, and belief of the true gospel and making changes in one's life to conform to the new way.
Martin G. Collins
Basic Doctrines: Repentance
God sent true ministers to the people, who believed His words from their mouths and obeyed the true doctrines. Seeing God's promises, they adopted the way of life that leads to their fulfillment. By their daily actions, walking in the footsteps of the apostles and Jesus Christ, they expressed living faith toward God, were baptized, and received the earnest of His Spirit toward salvation.
Martin G. Collins
Basic Doctrines: Faith Toward God