Acts 2:4

And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance.

And they were all filled with the Holy Spirit, and began to speak with other tongues - real, living languages, as is quite plain from what follows;

As the Spirit gave, [ edidou (G1325)] - or 'continued giving'

Them utterance - implying a prolonged exercise of this stings faculty. The thing uttered-perhaps the same by all-was "the wonderful works of God" (Acts 2:11), possibly in the language of the evangelical Hymns of the Old Testament: at all events, it is clear that the speakers themselves understood nothing of what they uttered.

The Astonishment of the Multitude (2:5-11)