Inter-church involvement is great – but it doesn’t make Christians united (because Christians are, by nature of our union with Jesus, ALREADY united) – but it is one (of many good ways) we can express the unity Christians have. Let me stress that it is only ONE possible way and that there are many other ways of expressing this, not the least through prayer… Some will say, “But people can’t see and experience the unity expressed through prayer! Our unity should be visible.” I agree, however, I disagree on to whom it should be visible. Our expressions of unity should be visible first to God, and second to the rulers and authorities in the heavenly realms (who I assume see what we do in secret):
This mystery is that through the gospel the Gentiles are heirs together with Israel, members together of one body, and sharers together in the promise in Christ Jesus… this mystery was for ages past kept hidden in God, who created all things. His intent was that now, through the church, the manifold wisdom of God should be made known to the rulers and authorities in the heavenly realms (Eph 3).
So, care less about showing the world that the church on this street corner and the church on that street corner can “do things” together, and instead, live for the glory of the God who is showing you off in the court-room of heaven. Love Jesus, love people, love each other. Be united in eternal purpose and hope and faith. Don’t get caught up in some felt need to “look” united in the eyes of the world – they really don’t care.