Dietrich Bonhoeffer said of discipleship,
Follow me, run along behind me! That is all. To follow in his steps is something which is void of all content. It gives us no intelligible programme for a way of life, no goal or ideal to strive after. It is not a cause which human calculations might deem worthy of our devotion, even the devotion of ourselves. . . .
The old life is left behind, and completely surrendered. The disciple is dragged out of his relative security into a life of absolute insecurity (that is, in truth, into the absolute security and safety of the fellowship of Jesus), from a life which is observable and calculable (it is, in fact, quite incalculable) into a life where everything is unobservable and fortuitous (that is, into one which is necessary and calculable), out of the realm of finite (which is in truth infinite) into the realm of infinite possibilities (which is the one liberating reality).
Again it is no universal law. Rather it is the exact opposite of all legality. It is nothing else than bondage to Jesus Christ alone, completely breaking through every programme, every ideal, every set of laws. No other significance is possible, since Jesus is the only significance. Beside Jesus nothing has any significance. He alone matters. (The Cost of Discipleship, p. 58-59)