Acts 2:8

How hear we every man in our own tongue - Some have supposed from this that the miracle was not so much wrought on the disciples as on their hearers: imagining that, although the disciples spoke their own tongue, yet every man so understood what was spoken as if it had been spoken in the language in which he was born. Though this is by no means so likely as the opinion which states that the disciples themselves spoke all these different languages, yet the miracle is the same, howsoever it be taken; for it must require as much of the miraculous power of God to enable an Arab to understand a Galilean, as to enable a Galilean to speak Arabic. But that the gift of tongues was actually given to the apostles, we have the fullest proof; as we find particular ordinances laid down by those very apostles for the regulation of the exercise of this gift; see 1 Corinthians 14:1, etc.

Wherein we were born - That is, as we say, in our native language; what is spoken where we were born.