The signs of Pentecost and what they point to are profound.  Fire was the sign of heart cleansing (Acts 15:9).  Uninterpreted languages (dialects) was the sign of a universal and non-provincial gospel for all ethnic and language groups.  Prophetic powers for proclamation given to rich and poor, master and slave, male and female were a sign that the Spirit is needed by all and available to all.  The mighty wind was the sign the Spirit was ushering in new creation (Genesis 1:2).  The fact of the Spirit’s outpouring was a sign that the crucified, resurrected and ascended Christ was in heaven and had poured out the “promise of the Father” (Luke 24:49).

“This Jesus God raised up, and of that we all are witnesses.  Being therefore exalted at the right hand of God, and having received from the Father the promise of the Holy Spirit, he has poured out this that you yourselves are seeing and hearing.” Acts 2:32-33 (ESV)