John Calvin Commentary Acts 19:4

"And Paul said, John baptized with the baptism of repentance, saying unto the people that they should believe on him that should come after him, that is, on Jesus." — Acts 19:4 (ASV)

John truly, Paul’s admonition aimed at this end: that these men, being convicted of their ignorance, might desire to go forward. He says that John preached of Christ who was to come. Therefore, he sent out his disciples so that, running in the course, they might go towards Christ who was not yet revealed.

For this reason, so that these men may not flatter themselves and refuse to go forward, he shows that they are still far from the mark. Indeed, the feeling of need compels men to desire what is still lacking.

The substance of it is this, as if Paul had said: Before Christ was glorified, this power of His did not appear in the world; when He ascended into heaven, He intended for His kingdom to flourish in this way.

Therefore, the graces of the Spirit were much less poured out when John was still in the course of his ministry—graces which now declare that Christ sits at the right hand of His Father, because He had not then openly shown Himself to be the Redeemer of the world.

Therefore, know that you must go further forward, because you are far from the mark. So he plainly shows that the faith of the godly, who had been taught by John, ought to have looked to Christ who was to come, lest these men should stand still, having newly entered, without going any further.

And by this we are also taught that the baptism of John was a sign of repentance and remission of sins. Furthermore, our baptism today does not differ at all from it, except that Christ is already revealed, and in His death and resurrection our salvation is made perfect.

Thus, baptism was brought to its effect. This is because repentance flows from that fountain of Christ’s death and resurrection, of which I have spoken. Faith is also directed to that fountain, so that it may seek free righteousness from there.

In summary, Paul plainly shows that John’s baptism was the baptism of regeneration and renewal, just as ours is. And because both purging and newness of life flow from Christ alone, he says that it was grounded in faith in Him.

By these words we are also taught that upon this faith in Him depends all the force of baptism: namely, that by faith in Christ we lay hold of whatever baptism signifies. So far is it from being true that the outward sign detracts from or diminishes the grace of Christ by a single iota.