In the fall of 1933 Bonhoeffer moved to London to take up the pastorate at two German congregations. In October, just after taking up these positions, he penned a letter to Karl Barth, asking Barth’s opinion of his decision. Here are excerpts:

Dear Professor Barth,

I am writing you the letter that I meant to write six weeks ago and which would then, perhaps, have had entirely different consequences for the course of my personal life. Why I did not write then is almost incomprehensible to me now. I know that only two things were factors at that time. I knew that you were busy with a thousand other matters, and it seemed to me, during those heated weeks, that the fate of one individual was so utterly trivial that I simply could not imagine it being important enough to write about to you. Second, however, I think there was also a bit of fear involved. I knew that I would simply have had to do what you would have told me, and I wanted to be free, so I suppose I simply withdrew. Today I know that that was wrong and that I must beg your pardon. I made my decision “freely,” but without really being free in relation to you…

Now I have been here eight days, have to preach every Sunday, and get news almost every day from Berlin as to how things stand. It’s enough to tear one apart. And now you will soon be in Berlin, and I cannot be there. I even feel as though, by going away, I have been personally disloyal to you. Perhaps you won’t be able to understand this at all, but for me it is an enormous reality.

I have no idea yet how long I shall have to stay on here. If I knew I was really needed there in Berlin–it’s so terribly hard to know what we should do. “We do not know what to do, but…” 2 Chronicles.

So, now this letter has been written. These are only personal matters, but I did want you to know about them. If I were ever to hear a word from you again, it would be wonderful. I think a great deal about you and your work and where we should be without it. Would you be so kind as to write me your very honest opinion of all this? I think I would be open even to sharp words and grateful for them.

Barth responded to Bonhoeffer’s letter about one month later, in late November. His response is colored and memorable, containing the sharp words that Bonhoeffer said he would appreciate:

My dear colleague,

From this salutation you will gather that I have no intention of regarding your going off to England as anything other than a perhaps personally necessary interlude. Since your mind was set on this, you were quite right not to seek any wisdom from me before doing it. I would have advised against it, unconditionally and certainly bringing up the heaviest artillery I could muster. And now that you come to me with this after the fact, I truly cannot do otherwise than call to you, “Get back to your post in Berlin straightaway!” What is this about “going into the wilderness,” “keeping quiet in the parish ministry,” and so forth at the moment when you are needed in Germany? You, who know as well as I do that the opposition in Berlin, indeed the church opposition in Germany as a whole, is on such shaky ground spiritually! That every honest man should have his hands fully with making it sharp and clear and solid!…

What’s the point in singing my praises–from the other side of the Channel? What’s the point of the message I received from your student, just as I was in the midst of tussling with out splendid “Council of Brethren” of the Emergency League–instead of your being here and standing up to these brethren along with me…Why weren’t you there  pulling together on the rope that I, virtually alone, could hardly budge? Why aren’t you here all the time, when there is so much at stake that calls for a few brave souls to keep watch, whether the occasion is great or small, and try to save whatever can be saved? Why, why? You see, as I said, I’m quite ready to assume that your going away was personally necessary for you. But I would then ask, what does “personal necessity” actually mean at this moment? Reading your letter, I believe I can see that you, like the rest of us–yes, all of us!–are suffering under the enormous difficulty of “making straight paths for our feet” through the present chaotic situation. But shouldn’t it be clear to you that this is no reason to withdraw from the chaos; that perhaps we are called to man our positions in and with our uncertainty, even if we stumble and go astray ten or a hundred times over, or however well or badly we then serve our cause? I am simply not happy with your putting your own private problem at center stage at this point, in view of what is at stake for the German church today. Won’t there be time enough afterword, when, God willing, we are beginning to come out on the other side of this mess, to work off the various complexes and scruples from which you are suffering, as others are suffering as well? No, to all the reasons and apologies that you may still have to offer, I can only and shall always have the same answer: And what of the German church? And what of the German church?–until you are back in Berlin, manning your abandoned machine gun like a loyal soldier…

Since you have written me only that you are now over there, I will write you, for now, nothing more than just this: that you should be back in Berlin.

DBW 13 (1/2, 1/16), London: 1933-1935, Minneapolis: Fortess Press (2007)