Did the twelve disciples at Pentecost speak only regional languages or also local dialects?
At Pentecost, the twelve disciples spoke not only regional languages but also local dialects. The Greek word behind “tongues” is dialectos, indicating they brought the languages down to the dialect of individual areas so that everyone could understand every word.
Les teaches in Acts chapter 2 that on the Day of Pentecost, Jews had congregated from all over the then-known world. He points out that the Greek word for tongues is dialectos, from which we get dialect. So the twelve disciples did not speak only a regional language; they spoke down to the dialect of individual areas. Les emphasizes that these were common, ordinary Galileans, not highly educated or cultured, yet they had been with the Lord for three years and were given this ability. They spoke all these languages down to the local dialect so the people could understand every word. Les contrasts this with someone who can speak seven or eight languages, noting that such a person seems intelligent, but these men received a miraculous ability from God.