John Calvin Commentary Acts 13:24

"when John had first preached before his coming the baptism of repentance to all the people of Israel." — Acts 13:24 (ASV)

We know what office John had, namely, to prepare the way of the Lord. Therefore, Paul brings in his testimony so that he might prove to the Jews that he preached no false Christ, but the true Christ of God, whom that most famous forerunner had previously commended.

It is not that man’s testimony is sufficient to prove so weighty a matter; rather, John was regarded with special respect, as almost all men considered him to be a prophet of God. Therefore, from this comes the authority of the testimony: that a herald sent from heaven, and no private man, speaks of Christ.

And Paul recites two things summarily concerning John:

1. that he taught the baptism of repentance before Christ’s coming;
2. that, casting from him of his own accord the title and honor of the Messiah, he submitted himself to Christ.

The baptism of repentance. Baptism introduced contrary to the rite and custom of the Law was a token of great alteration, for it was unlawful to renew anything before Christ’s coming. The Jews indeed had their baptisms or washings in the Law, which were also exercises of repentance, but John was the author of a new and strange baptism—or rather the minister—who gave them hope of the restoration long looked-for and desired. When he calls it the baptism of repentance, he does not exclude remission of sins, but he speaks according to the circumstance of the place, because this baptism was a preparation for faith in Christ. And we must note the phrase that he preached baptism. By this we are taught that the sacraments are then rightly administered when doctrine is joined with the visible figure; for the mouth of the baptizer must not be silent, because the sign is vain without doctrine.