Fear and Trembling is a philosophical work by 
Soren Kierkegaard, published in 
1843 under the pseudonym [[Johannes 
de silencio]]. 
The title is apparently a reference to 
Philippians 2:12: "...continue to work out your salvation with fear and trembling."
The work begins with a meditation on the faith of 
Abraham when he was commanded by 
God to sacrifice his son 
Isaac, as told in 
Genesis chapter 22. 
Then follow the "Problemata," which address three specific philosophical questions raised by the story of Abraham's sacrifice:
-  Is there a teleological[?] suspension of the ethical? (That is, can Abraham's intent to sacrifice Isaac be considered "good" even though, ethically, human sacrifice is unacceptable?)
-  Is there an absolute duty to God?
-  Was it ethically defensible of Abraham to conceal his purpose from Sarah, from Eleazar, from Isaac?
In Fear and Trembling, Kierkegaard introduces the "knight of faith" and contrasts him with the "knight of infinite resignation." 
The latter gives up everything for a great cause and continuously dwells with the pain of his loss.
The former, however, not only relinquishes everything, but also trusts that he will receive it all back, his trust based on the "strength of the absurd."
 
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