New Defender's Study Bible Notes
19:3 John’s baptism. Paul here simply assumed they had been baptized, since they had believed and were disciples. In the New Testament, baptism always immediately followed saving faith, and is then followed by discipleship. This is the only case mentioned in the New Testament of anyone being “rebaptized.” Not even Apollos, who also had known “only the baptism of John” until Aquila and Priscilla gave him further instruction (Acts 18:25-26) needed to be rebaptized. The same was true of the twelve apostles. Presumably the difference was that the Ephesian disciples had been baptized by one or more of John’s disciples after the coming of the Holy Spirit at Pentecost when Christ’s disciples first began to baptize “in the name of Jesus Christ” (Acts 2:38). Also, this was an important new stage in the spread of the gospel, with Ephesus destined to become a center like Antioch and Jerusalem. It was important that the ministry of John be thus tied in with that of Christ once and for all by a manifestation of the Holy Spirit as at Jerusalem and Antioch and in the house of Cornelius.