Before Jesus ascended into heaven, He told His apostles that they would “receive power when the Holy Spirit has come upon you…” (Acts 1:8)  They were not told when this would happen or how it would happen.  So they met together with other believers (120 men and women) and waited, and while they were waiting they prayed… 
(Acts 1:14; Acts 2:1)

The Day of Pentecost – the day of the revelation of the Acts of the Holy Spirit.
  Then one day, suddenly, as they were together in a house “there came from heaven a noise like a violent rushing wind, and it filled the whole house where they were sitting.” (Acts 2:2)  Only the sound of wind, no effects of a violent rushing wind was felt. 

  First the sound of wind…then another work of God:
(NASB) Acts 2:3 “And there appeared to them tongues as of fire distributing themselves, and they rested on each one of them.”  

  Second tongues of fire resting on each person present – men and women.
Each person saw the tongues of fire on all those present…no one was burned or scorched. 

  Only God can do such a work.  God’s work is authentic.  God’s work is authoritative.  God’s work is accurate and according to His purposes and plan. 

  God always involves people in His purposes and plan.
  God reveals Himself in a way we can understand through seeing and hearing.
  God takes a complex concept and simplifies it so we can respond to Him. 

  Belief in Jesus – the starting point…
  Faith in Jesus – as you and I live out our lives each day. 

  The Lord God makes visible what He gives as an inward reality.
  Followers of Christ…we have been given the power of the Holy Spirit the moment we believed in Jesus as our Savior, Redeemer.   

Worship the living God.
  All praise and honor and glory belong to God alone.  God the Father, God the Son, God the Holy Spirit…three Persons yet one God.