Didn’t Bonhoeffer talk about “cheap grace”, by which he meant strict discipleship as described by the New Testament? Yes, in The Cost of Discipleship (1937), he wrote in that way. But six years later as he faced the hard realities of Nazi tyranny, and as he was personally involved in the plot to kill Hitler, he stepped back from his pietism in order to do what was needed, including lying and killing, to restrain evil. He rediscovered the calling of the Christian “to live completely in this world” without simplistic solutions. And in the brokenness of life he rediscovered “grace” as forgiveness found at the foot of the cross.