I feel I may have slightly misrepresented Bonhoeffer's views on my previous post. While I still stand by what I wrote, I'd like to clarify a few things.
My prior post was mainly focused on the doom and gloom of the human condition, but that is not quite true to Bonhoeffer's attitude and philosophy. He focused on the strength, not the weakness, of the human species, and on joy, gratitude, and fortitude instead of fatalism and resignation.
Perhaps I have incorrectly interpreted his meaning of the idea of "responsibility", but I believe he just considers it water under the bridge. That is to say, yes, the human sin problem is there, but God has that covered, so let's move on to other things.
When discussing responsible action, he says, "We must learn to act differently from those who always hesitate... we must be clear about what we want, we must ask whether we're up to it, and then we must do it with unshakable confidence. Then and only then can we also bear the consequences." Consequences, in this context, referring to the earthly consequences, of course. God will take care of the rest.
So while we do have to resign ourselves to God's grace, we are not to be ashamed that we behaved as responsibly as possible. We are called to behave as responsibly as possible.
Does that clear things up?
To close with a related line: "May God in his mercy lead us through these times; but above all, may he lead us to himself."