"They had no Bibles, no cemeteries, no Bible schools.

No radios or telephones.

No printing presses.

No churches.

Nothing!

However, they turned the world upside down in one generation.

What did they have?

They had an experience with the living Christ.

They had the filling of the Holy Spirit."

"And when they had prayed, the place in which they were gathered together was shaken, and they were all filled with the Holy Spirit and continued to speak the word of God with boldness." 

-  the early church in Acts 4.31 (ESV)