Acts 1:8 But you will receive power when the Holy Spirit has come upon you; and you will be my witnesses in Jerusalem, in all Judea and ...

... and Samaria, and to the ends of the earth.

In this one sentence, Luke gives us the outline of the entire Book of Acts. He might as well have said, “Look out Jerusalem, here we come! Look out Judea and Samaria, look out ends of the earth, Here we come!! They were indeed his witnesses in all of those destinations.