According to Johhanes Climacus, though the ethical is not absent from the religious person’s concerns, what separates the two spheres is the manner in which the religious person (in particular, the Christian) relates to God. As C. Stephen Evans explains,
[h]er relation to God […] consists primarily not in self-confident action but in repentance. Her task is not primarily to achieve a God-relationship herself by positively realizing her moral duty, but to achieve a sate of inward obedience to God by allowing God to transform her character. This is well illustrated by Fear and Trembling where Johannes de Silentio claims that “an ethic which ignores sin is an absolutely idle science, but if it acknowledge sin, then it eo ipso transcends itself” (III, 146; p. 108). The reason for this is given in a footnote attached to the same paragraph: “As soon as sin appears, ethics perishes, precisely because of repentance; for repentance is the highest ethical expression, but precisely as such the deepest ethical self-contradiction” (III, 146n, p. 108n).
 C. Stephen Evans. Kierkegaard’s Fragments and Postscript: The Religious Philosophy of Johannes Climacus, (New York: Humanity Books, 1999), 140.