Jews were spread all over the world by the time the Holy Spirit showed up at the Pentecost celebration held after Jesus died and was resurrected.  Many of those nations were represented at the festival – Acts 2 says “every nation under heaven,” and specifically mentions “Parthians and Medes and Elamites and residents of Mesopotamia, Judea and Cappadocia, Pontus and Asia, Phrygia and Pamphylia, Egypt and the parts of Libya belonging to Cyrene, and visitors from Rome, both Jews and proselytes, Cretans and Arabians.” 

These people from places way beyond Jerusalem heard the commotion of the believers speaking in tongues and they understood the apostles in their native language!  They were “All amazed and perplexed.” This is certainly part of the Holy Spirit providing the Power (Acts 1.8). And it had to leave a lasting impression on those involved. 

Some of these visitors or alien residents believed in Jesus Christ that day and became part of the early church in Jerusalem.  Some returned home immediately after.  They all must have been sharing the story around the dinner table, at the local bar, over the water cooler at work, across the back yard fence, etc.  The rest of the book of Acts follows a few of the apostles, particularly Paul and his friends, to testify that the gospel reached Rome. 

But all these Pentecost hearers had spread the word far and wide even without Paul.  The groundwork had been laid, the topic introduced, and curiosity peeked.   The Apostles were to be the witnesses to Jerusalem, Judea and Samaria, and the ends of the earth; they were to entrust the gospel to faithful men who would pass it on to other faithful men.  And, the Holy Spirit was planting seeds all over the world based on the power shown at Pentecost.  What a plan!