"Discipleship is commitment to Christ. Because Christ exists, he must be followed. An idea about Christ, a doctrinal system, a general religious recognition of grace or forgiveness of sins does not require discipleship. In truth, it even excludes discipleship; it is inimical to it. One enters into a relationship with an idea by way of knowledge, enthusiasm, perhaps even by carrying it out, but never by personal obedient discipleship. Christianity without the living Jesus Christ remains necessarily a Christianity without discipleship; and a Christianity without discipleship is always a Christianity without Jesus Christ. It is an idea, a myth. A Christianity in which there is only God the Father, but not Christ as a living Son actually cancels discipleship. In that case there will be trust in God, but not discipleship."
- Dietrich Bonhoeffer (from "Discipleship", Fortress Press, 2003, p. 59)