Pentecost is the New Testament name for the Feast of Weeks.
Just as Passover is associated with the exodus from Egypt, so is Pentecost associated with the renewal of the covenant with Noah and then with Moses.
When the Holy Spirit came the wind filled the house it definitely brings to mind Old Testament Theophanies (a visible manifestation to humankind of God) (Especially when the Red Sea split)
The second symbol of the Holy Spirit was fire. Again the analogy reminds us of Old Testament Theophanies (Especially from Sinai/burning bush))
Now we must assume that the disciples moved outside from the upper room and came in contact with the crowd that had assembled in Jerusalem for the feast.
The sound that the disciples were making probably confused the crowd since they could not understand how they could understand each other.Â
Now the two main languages spoken at the time would be Aramaic and Greek. Which the disciples would have spoken both of these languages.Â
What was significant was that the various vernacular languages of these people were being spoken.
Luke gives us a list of the different nations present from the Roman Empire:
* Persia(modern Iran), Mesopotamia (modern Iraq), Judea, Asia Minor (modern Turkey), Egypt, Rome, Crete, and Arabia.
Now all of the people present were either Jews or converted Jews (Proselytes - A person who has converted from one religion to another)
The primary reaction was one of incomprehension. This gave Peter the prime opportunity to address the crowd and share the Gospel.