When the proponents of one Christian tradition assume that it holds in its hands all the resources needed for the flourishing of the church, and when we read other traditions in reductive and simplistic ways, then we are unnecessarily impoverishing ourselves and weakening our cause.
As one of my mentors would say, "We are all different regiments in God's army." Many bemoan the fact that we have so many different denominations, but one thing I drew from my experiences at an inter-denominational seminary, Beeson Divinity School, is that each regiment has specialties that serve the greater community of God.
I see at least two benefits. First, I need the voice of my Baptist, Catholic, Methodist, Pentacostal, and Prebyterian brothers and sisters to make sure that I stay true to the core doctrines of Christian faith. The histories and cultures of other denominations provide a unique perspective from which my own theological and pragmatic blind spots can be spotted. If I ever sway from orthodox belief, my friends will steer me back on course.
Second, diversity inspires innovation. The problems I face in my own life and the life of our church are well aided by the voices of other travelers. As long as we hold tight to the essentials of our faith, then we become more willing to listen to each other's thoughts and solutions. My tradition might not have a history that fully equips me for addressing every issue, and so I can borrow from the experiences of others.
And as Jacobs points out, we're especially going to need each other as we move into this next era of God's people.