(also, baptism of fire)
Meaning: an ordeal, especially of martyrdom; soldier’s first battle experiences (definition).

Example: On his first day, the customer service rep faced a first rate consumer rage call, an epic baptism of fire.


Origins: First used in French to reference a soldier’s experience in battle, 1822. Also Biblical references. (Source.)

Rewrites:

baptism by conflagration blessing by bayonet passion by ambush ecstasy by battle immersion by Armageddon purification by scrabble
Discussion: There are a couple of different ways to go with this idiom. Be inventive.