Bonhoeffer's theologically rooted opposition to National Socialism first made him a leader, along with Martin Niemueller and Karl Barth, in the Confessing Church (bekennende Kirche), and an advocate on behalf of the Jews. His leadership in the anti-Nazi Confessing Church and his participation in the Abwehr resistance circle make his works a unique source for understanding the interaction of religion, politics, and culture among those few Christians who actively opposed National Socialism.
Bonhoeffer was condemned for his involvement in "Operation 7," a rescue mission that had helped a small group of Jews over the German border and into Switzerland. He had also been involved in planning an unsuccessful assassination attempt on the life of Adolf Hitler. His participation in the murder plot conflicted with Bonhoeffer's position as a pacifist. He explained: "If I see a madman driving a car into a group of innocent bystanders, then I can't, as a Christian, simply wait for the catastrophe and then comfort the wounded and bury the dead. I must try to wrestle the steering wheel out of the hands of the driver." He was hanged in the concentration camp at Flossenbürg on April 9, 1945, at the age of 39, one month before the end of the war. He was one of four members of his immediate family to die at the hands of the Nazi regime for their participation in the small Protestant resistance movement. The letters he wrote during these final two years of his life were posthumously published by his student and friend, Eberhard Bethge, as Letters and Papers from Prison.