What does Mark 1:8 mean?

Being baptized with water is no small thing. The mikveh is a ceremonial stepped bath, still used by devout Jews for ceremonial cleansing. This is performed before a marriage, after birth or menstruation, or for converts who wish to wash away their old lives and beliefs and follow Judaism. John's baptism is one of "repentance." He encourages the people to ask God to forgive their sins and change their way of thinking. They should seek to fight against the sinful lifestyle they'd grown used to. By being baptized by John in the Jordan River, the people agree with his message and promise to turn away from their sins.

John's message is counter-cultural on two sides. The Pharisees and Scribes—the local religious leaders—place heavy legalistic burdens on the people. By comparison, John's simple call to repent seems almost too easy. On the other hand, John convicts the people to reject the decadent lifestyle of their political masters: the Romans.

John's message also promises that the Messiah, the Jewish savior, offers a far more powerful baptism: that of the Holy Spirit. The "baptism of the Holy Spirit" is the moment when a person trusts Jesus to forgive their sins and make them right with God. In an instant the Holy Spirit comes into the new believer to provide insight into the Christian life (John 16:13), gifts to help other believers (1 Corinthians 12), and a change in our beliefs and actions so we can serve God and others better (Galatians 5:22–23).

The church has spent centuries debating when this baptism first happened. The first possibility is that John refers to the incident at Pentecost when "there came from heaven a sound like a might rushing wind" and Jesus' followers were filled with the Holy Spirit (Acts 2). The second possibility is that we are baptized with the Holy Spirit at the point of salvation (1 Corinthians 12:12–13). Third, some view baptism with the Holy Spirit as an independent event which believers experience after salvation—a personal "Pentecost" experience after the point of salvation. Still others suggest a future baptism of the Holy Spirit connected with Christ's return (Isaiah 44:3; Joel 2:28–32).

Both the first and second interpretations are biblically supported. The baptism of the Holy Spirit first took place on the Day of Pentecost for those who were already following Christ (Acts 2:1–4). In the modern church, all believers receive this "baptism" when they come to faith in Christ (1 Corinthians 12:12–13). The only apparent exception to this is the partial dispensation of the Holy Spirit, given by Jesus to the disciples in John 20:22.