v 8. But you will receive power when the Holy Spirit comes upon you. And you will be my witnesses, telling people about me everywhere—in Jerusalem, throughout Judea, in Samaria, and to the ends of the earth.
This instruction sets the agenda for the rest of the New Testament. It follows on from what we read in Matthew 28:18-20 ‘ Therefore, go and make disciples of all the nations,‘ which we call ‘The Great Commission’.
It is more than a plain command however, it contains the promise of the coming of the Holy Spirit and the power to fulfil the mission purpose.