Fear and Trembling, written by Søren Kierkegaard as Johannes de Silentio, is fraught with the paradox of Abraham's ordeal on Mount Moriah. Through the investigation and extension of these paradox, Kierkegaard brings the idea of faith into sharper focus. When Abraham's test of faith is scrutinized, it becomes clear that there is more involved in faith than simple belief. Faith involves the acceptance of its inherent paradox, and the solitude these paradox incur.
Kierkegaard describes the many facets of Abraham's faith in such a way as to delineate between true faith, embodied in one he calls the "knight of faith," and mere resignation, which is present in those such as tragic heroes. Kierkegaard understands that a state of resignation is attainable. In fact, he goes so far as to say that he would not hesitate to deem anyone who does not, at least try to achieve this state a coward. He views resignation as a necessary predicate for faith, but for him it is unfathomable how the leap can be made between resignation and faith. For Kierkegaard, the one who does traverse this chasm is the truly great. In this manner, he portrays Abraham in a light in which he shines more brightly than any Agamemnon or Jephthah.
A fundamental difference between the knight of faith and the tragic hero involves the suspension of the ethical. "The tragic hero is still within the ethical" (p. 59), while the knight of faith must surpass it. In Abraham's case, there is a suspension of the ethical. This suspension of the ethical is one of the main points Kierkegaard utilizes to accurately depict how difficult it would truly be to become and remain a knight of faith. In Abraham's ordeal, he transgresses the ethical in his resignation. He sets out to sacrifice his only beloved son, Isaac. His sacrifice violates the father's highest duty to his son, which is to love and protect. The difference between Abraham and the tragic hero, the difference which sets Abraham apart as a knight of faith, involves the fact that Abraham's actions do not serve the universal:
For I certainly would like to know how Abraham's act can be related to the universal, whether any point of contact between what Abraham did and the universal can be found other than that Abraham transgressed it. (p. 59)
Abraham's actions in resigning to sacrifice his son did not serve a higher purpose, at least in the ethical sense. "It is not to save a nation, not to uphold the idea of state that Abraham does it; it is not to appease the angry gods" (p. 59). Thus, Abraham could not take shelter beneath the hope that his actions were morally virtuous. It is the fact that they are personally virtuous, however, that make him a knight of faith. As Kierkegaard states, Abraham is either a knight of faith or a murderer.
The paradox deepens when Abraham's ordeal is examined further. God asks that Abraham sacrifice Isaac as a test of faith. In order for this to be a true sacrifice, Abraham's love for Isaac must exceed his love for God, otherwise Abraham would be happy to serve God, whom he loved the more. Yet, if he loved Isaac more, why then would he set out on the journey to Mount Moriah? The paradox is unrelenting unless the individual's relationship with God is perceived as one of absolute duty:
In this connection, to say that it is a duty to love God means something different from the above, for if this duty is absolute, then the ethical is reduced to the relative. (p. 70)
Because of the suspension of the ethical, and because of the difference between resignation and true faith, Kierkegaard believes that the life of the knight of faith is extremely trying and impossible for others to understand. At no time is Abraham ethically understandable to his peers or even to his household, for if he admits that his ordeal is merely a test of faith, he has lost. He must continue on to Mount Moriah, resigned to sacrifice Isaac, but still faithful in the absurd: that in his sacrifice, he will have his son. This, for Kierkegaard, is what elevates Abraham to the status of one who is truly great.