6 And at this sound the multitude came together, and they were bewildered, because each one heard them speaking in his own language. 7 And they were amazed and wondered, saying, "Are not all these who are speaking Galileans? 8 And how is it that we hear, each of us in his own native language?
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.