Baptisms were not uncommon in Judaism. Washing is a sign of cleansing and the Jews had a number of washing rituals. John’s baptism was a baptism of repentance. John’s baptism did not bring with it the regeneration by way of the Holy Spirit. There are a number of verses of scripture that point this out. Perhaps the most clear is in the book of Acts which explains why some folks were re-baptized in the Trinitarian formula if they had only been baptized in the baptism of John. The following passage will be helpful:
Acts 19:1-7
WHILE APOLLOS was at Corinth, Paul passed through the upper country and came to Ephesus. There he found some disciples. And he said to them, “Did you receive the Holy Spirit when you believed?” And they said, “No, we have never even heard that there is a Holy Spirit.” And he said, “Into what then were you baptized?” They said, “Into John’s baptism.” And Paul said, “John baptized with the baptism of repentance, telling the people to believe in the one who was to come after him, that is, Jesus.” On hearing this, they were baptized in the name of the Lord Jesus. And when Paul had laid his hands upon them, the Holy Spirit came on them; and they spoke with tongues and prophesied. There were about twelve of them in all.
