Christ] was not, like a philosopher, interested in the ‘universally valid,’ but rather in that which is of help to the real and concrete human being. What worried Him was not, like Kant, whether ‘the maxim of an action can become a principle of general legislation,’ but whether my action is at this moment helping my neighbor to become a man before God. He continued: What can and must be said is not what is good once for all, but the way in which Christ takes form among us here and now. The attempt to define that which is good once for all has, in the nature of the case, always ended up in failure.
Ethics, Bonhoeffer