Getting back to Barnabas and Saul, they “returned from Jerusalem when they had completed their service, bringing with them John, whose name was Mark” (12:25). In every effective mission assignment, we should know when his/her assignment in a place is finished. Paul never stayed in one place very long and the most was three years (Ephesus – Acts 20:31). True, it was only delivering a gift for the elders to use for those in need, but Jerusalem may have been tempted to keep them there for some reason. God had a plan that John Mark should join them for the next assignment. If they had stayed in Jerusalem, the advancement of the gospel into other regions of Asia and Europe may have been hindered.
How do you see the Holy Spirit guiding your ministry so that we can accelerate the gospel to the unengaged and unreached? Let God make you more effective for His glory!