Acts 1-5: What is this Power?

For forty days after he was crucified and rose again, Jesus appeared to the disciples in various places. “Do not leave Jerusalem," he told them, "but wait for the gift my Father promised, which you have heard me speak about For John baptized with water, but in a few days you will be baptized with the Holy Spirit - Acts 1:4-6(NIV)  All they wanted was to see the kingdom of Israel restored.  Instead, He said to them: “It is not for you to know the times or dates the Father has set by his own authority. But you will receive power when the Holy Spirit comes on you; and you will be my witnesses in Jerusalem, and in all Judea and Samaria, and to the ends of the earth.”  - Acts 1:7-3

What is this power that the disciples and early church experienced after Jesus ascended into heaven, power that appeared at Pentecost that sounded like a blowing wind and filled the room with what looked like tongues of fire?  What was this power that gave Peter, the one who had denied Jesus three times, the boldness to stand up and address the crowd that gathered in Jerusalem with such boldness that three thousand accepted the message and were baptized that very day..  What was this power that enabled Peter to heal the crippled beggar?  What gave Peter and John boldness before the Sanhedrin, the ones responsible for Jesus' death?  What was the power that caused Ananias and Sapphira to fall down dead for lying to the apostles about how much money they received for the sale of some land.  What was the power that opened the prison gates for the apostles. 

It was the same power that caused men to face death boldly when thrown to the lions.  The power that enabled all the martyrs down through the centuries to go to their deaths willingly.  The power that has caused thousands of missionaries to sacrifice their lives that the gospel would be heard.  The power that has healed the deaf, blind, and lame down through the centuries.  The same power that gave Handel the "Messiah". The power that changed the slave trader who eventually wrote "Amazing Grace". 

It is the Holy Spirit, Peter told the crowd.  The Holy Spirit that Jesus promised would come  God has raised this Jesus to life, and we are all witnesses of it. Exalted to the right hand of God, he has received from the Father the promised Holy Spirit and has poured out what you now see and hear. - Acts 2:32-33 NIV

The power of Jesus and the resurrection was now available for all that believed.