First job-finder for the unemployed (5)

I believe the answer is:

satan

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'first' is the definition.
Although both the answer and definition are singular nouns, I can't see how one could define the other.

I don't understand the remainder of the clue.

Can you help me to learn more?

(Other definitions for satan that I've seen before include "Prince of Darkness" , "arch-fiend" , "Apollyon" , "Old Nick, Lucifer or Beelzebub" , "Fallen archangel" .)

I've seen this clue in The Guardian and The Globe and Mail.

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