Calvin on Acts 2:4...
Some seem to be fully convinced that Peter was preaching in tongues. Is that a good and necessary inference?
I suppose that it doth manifestly appear hereby that the apostles had the variety and understanding of tongues given them, that they might speak unto the Greeks in Greek, unto the Italians in the Italian tongue, 82 and that they might have true communication (and conference) with their hearers. Notwithstanding, I leave it indifference whether there was any second miracle wrought or no, so that the Egyptians and Elamites did understand Peter speaking in the Chaldean tongue, as if he did utter divers voices. For there be some conjectures which persuade me thus to think, and yet not so firm but that they may be refuted. For it may be that they spoke with divers tongues, as they light upon this man or that, and as occasion was offered, and as their languages were diverse. Therefore, it was a manifest miracle, when they saw them ready to speak divers languages. As touching Peter’s sermon, it might be understood of the greater part of men wheresoever they were born; for it is to be thought that many of those which came to Jerusalem were skillful in the Chaldean tongue. Again, it shall be nothing inconvenient if we say that he spoke also in other tongues. Although I will not much stand about this matter; so that this be out of doubt, that the apostles changed their speech.
Some seem to be fully convinced that Peter was preaching in tongues. Is that a good and necessary inference?