Derrida's main concern is with the meaning of moral and ethical responsibility in Western religion and philosophy. He questions the limits of the rational and the responsible that one reaches in granting or accepting death, whether by sacrifice, murder, execution, or suicide. Beginning with a discussion of Patocka's Heretical Essays on the History of Philosophy, Derrida develops Patocka's ideas concerning the sacred and responsibility through comparisons with the works of Heidegger, Levinas, and, finally, Kierkegaard. Derrida's treatment of Kierkegaard makes clear that the two philosophers share some of the same concerns. He then undertakes a careful reading of Kierkegaard's Fear and Trembling, comparing and contrasting his own conception of responsibility with that of Kierkegaard, and extending and deepening his recent accounts of the gift and sacrifice. For Derrida, the very possibility of sacrifice, especially the ultimate sacrifice of one's own life for the sake of another, comes into question.