Abraham would have been terrifying because if we had met him we would never have glimpsed his inner life. We would not have seen the man of faith. We would have seen a man who was prepared to murder his son.

Traditionally, when the story is told, the faith of Abraham is emphasised. Abraham had such faith that he would not withhold from God even his own son. God rewards him for his faith.

The Bible tells us: God never intended to let Abraham murder his son, he was just testing Abraham’s faith. But Abraham didn’t know this at the time. He was preparing to murder his son.

It would have been hard for Abraham to explain his actions to anyone but God Himself. But being a man of faith, Abraham never felt he had to.

But what is terrifying is that Abraham would have been in all outward respects indistinguishable from a maniac. If a man today planned to murder his son, and told us that God had told him to do it, we would not praise that man as a man of faith.

In Fear and Trembling, Kierkegaard posits such a man. He is called “the sleepless man”. He hears the story of Abraham told at church. He’s so possessed by the story he cannot sleep. He resolves “to do just as Abraham had done”. The pastor gets wind of this just in time, calls the man “abominable man, scum of society” and sees to it that he’s arrested. The man will spend the rest of his days in a mental institution or awaiting the death penalty. (263)

Kierkegaard’s point is that the pastor is caught in a contradiction: he wants to praise Abraham but will not praise the man who would do as Abraham did. (264)

The inner life is not easy to recognise by any outward signs, is the message of Fear and Trembling. No-one can know the faith that drives Abraham to plan this terrible act except Abraham himself. In the same way, the pastor cannot know whether it is faith that drives the sleepless man to his own monstrous resolution. You either praise neither man, or both. (264)

But there’s a problem with Kierkegaard’s argument. He re-tells the story of Abraham and Isaac 4 times, and the final time he suggests that Isaac could have noticed the “shuddering” of his father as he “clenched” his left hand “in despair”. By these signs Isaac would have known that his father ultimately lacked the faith to carry out the task. (257)

If Isaac can read the state of his father’s faith from his outward appearance, then there is some connection between a person’s inner and outer life, between his inner feelings and outward behaviour. And so there is in principle something that we can observe, something outward, by which we could distinguish the man of faith, acting on God’s command, from the maniac, driven by some inexplicable madness to copy the actions of Abraham without the justification that Abraham had (the command of God).

Garff points out that Kierkegaard never really clarifies the connection between the inner and outer life in his book. Fear and Trembling is not supposed to offer such an explanation because it starts off from a faulty premise: that inner and outer life are wholly separate. And because this premise is faulty, Kierkegaard can’t help but contradict this premise. (265)

By defending the sleepless man where the pastor and most other sane people would condemn him, Kierkegaard makes it seem that he is “the implacable defender of inwardness”, of the principle that only God can judge the intentions of human beings. But Garff seems to suggest that if Kierkegaard ever intended to argue this he didn’t do so for long. Garff tells us that the absurd and contradictory argument in Fear and Trembling is a sign that Kierkegaard is going to move in his later work towards a philosophical position where inner and outer are connected. (265)

In Fear and Trembling, Kierkegaard was either deliberately writing from a philosophical position he didn’t really hold, or else he really did believe what he wrote but later moved on and rejected these views. Either way, we should not take Fear and Trembling to be the ultimate statement of Kierkegaard’s philosophical position.

(Numbers in brackets refer to pages in Joakim Garff (2005), Søren Kierkegaard: A Biography, trans. Bruce H. Kirmmse, Princeton University Press.)