Acts 19:1-7. Apollos has gone to Corinth, and Paul returns to Ephesus. Speaking to about twelve disciples there, he asks if they have received the Holy Spirit and they say they have never even heard of the Holy Spirit. Paul asks how they were baptized, and they reply "Into John's baptism." Paul tells them that "John baptized with the baptism of repentance, telling the people to believe in the one who was to come after him, that is, Jesus." The Ephesians then ask to be baptized in the name of Jesus Christ, and when Paul lays his hands on them, they speak in tongues and prophesy.

Chapter 19 of Acts is the beginning of Paul's third missionary journey. He returned to Jerusalem after leaving Ephesus the first time, and now he returns to Ephesus. This time he will stay longer. Paul begins his time there by visiting with twelve or so disciples, asking them how they've been baptized, and learning they've only received the baptism of John. When these disiples hear of the baptism in the name of Jesus, they ask for it, and they are ultimately baptized in the Spirit.

When Paul left Ephesus after a short first visit, Apollos came there and preached, but apparently Apollos did not baptize the Ephesians in the Spirit (or maybe he just missed these twelve disciples?). Remember that Apollos himself was only baptized in John's baptism, maybe I was wrong in assuming he was baptized in the Spirit while with Priscilla and Aquila. In any case, this is a very clear indication of the importance and true effect of baptism - the pouring out of grace and the gifts of the Holy Spirit are not perfected until we are baptized in the name of Jesus Christ.

John's baptism was preparatory, getting people ready for Christ, but the Holy Spirit on Pentecost fulfilled what baptism is supposed to be. Jesus Christ has come, we can know Him, he wants us to know Him, and, when we do, and we choose to be baptized in His name, He pours his Spirit upon us fully, just like the apostles at Pentecost. We cannot receive these gifts until we are baptized in his name, as the twelve disciples in Ephesus show us. I am sure it is no accident that there were twelve - we are seeing a mini-Pentecost to drive the point home!