The real issue relating to exclusiveness is whether or not the Christian actually has a relationship with God, a presence of God, which non-Christians do not have. Apart from Christian spiritual formation as described here, I believe there is little value in claiming exclusiveness for the Christian way.
Dallas WillardThe acid test for any theology is this: Is the God presented one that can be loved, heart, soul, mind, and strength? ... If it fails to set a lovable God--a radiant, happy, friendly, accessible, and totally competent being--before ordinary people, we have gone wrong
Dallas WillardTwo ways of thinking: Human kingdom and human cleverness or God's kingdom and God's cleverness
Dallas Willard