6 And when this sound was heard, the multitude came together, and were confounded, because that every man heard them speaking in his own language. 7 And they were all amazed and marvelled, saying, Behold, are not all these that speak Galilaeans? 8 And how hear we, every man in our own language wherein we were born?
Matthew Henry's Commentary on Acts 2:6-8
Commentary on Acts 2:5-13
(Read Acts 2:5-13)
The difference in languages which arose at Babel, has much hindered the spread of knowledge and religion. The instruments whom the Lord first employed in spreading the Christian religion, could have made no progress without this gift, which proved that their authority was from God.