Luke’s list of fifteen geographical locations was a group of nations or areas in which known Jewish populations existed and would likely have sent representative groups to the Feast of Pentecost.
Everyone there who spoke a language other than Greek or Aramaic heard the message of the Christians in that language—maybe fifteen languages, maybe fifty, maybe more.
The languages differed; the message remained the same: the wonders of God.
Pentecost was the first time that the Gospel was offered to every known nation on earth at one time.
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