Unto what then were ye baptized? — The answer of the disciples had shown (1) an imperfect instruction, falling short of that which catechumens ordinarily received before they were admitted to the new birth by water and the Spirit; (2) an imperfect spiritual experience. Could those who made it have been admitted into the Church of Christ by baptism in His name? The answer to that question showed their precise position. They were practically disciples of the Baptist, believing in Jesus as the Christ, and thinking that this constituted a sufficient qualification for communion with the Church of Christ.
Related Commentaries of Acts 19:3
Acts 19:3
3 And he said unto them, Unto what then were ye baptized? And they said, Unto John's baptism.