“And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance.”
King James Version (KJV)
2:4 And they began to speak with other tongues - The miracle was not in the ears of the hearers, (as some have unaccountably supposed,) but in the mouth of the speakers. And this family praising God together, with the tongues of all the world, was an earnest that the whole world should in due time praise God in their various tongues. As the Spirit gave them utterance - Moses, the type of the law, was of a slow tongue; but the Gospel speaks with a fiery and flaming one.
Ac 2:4 They were all filled with the Holy Spirit. All the disciples present. To be "filled" implies that the human spirit within was overwhelmed by, or immersed in, the Holy Spirit. The baptism of the Spirit was not a sprinkling, but an outpouring that overwhelmed the human spirit. Began to speak. This was the "Beginning". See Lu 24:47 Ac 11:15. With other tongues. "In other languages" (Revised Version). In the languages of all the different countries from which Jews had come up to Pentecost. Many would be unable to understand the Hebrew dialect of Judea in that period, and hence, they must be preached to in the tongue of their own country if they understood. That the gospel on this, the first day the Great Commission was ever preached, was preached in all tongues, symbolized the fact that it is for all nations. As the Spirit gave them utterance. They were not allowed to preach the Great Commission until now, in order that every word uttered on this day might be the word of the Spirit, not of man. The words were to be spoken to an audience, not of those in Jerusalem only, but to our whole race in all time, in order to show how sinners are to be saved under the gospel.