John Mark left them. It can be demoralizing when others abandon the mission-- it can even feel like betrayal. Some speculate that John Mark left because he opposed the mission of welcoming uncircumcised Gentiles into the family of God. Even without John Mark's departure, building bridges across old divides was going to be challenging. Paul's approach can show us the way forward in today's divided world -- let's start from common ground; let's build upon what others already believe.