A dictionary of Proverbs (Oxford Paperback Reference)

fingers see also the DEVIL makes his Christmas pies of lawyers’ tongues and clerks’ fingers.
FIRE is a good servant but a bad master

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  1615 T. ADAMS Englands Sickness 20 The world, like fire, may be a good seruant, will bee an ill Master. 1738 SWIFT Polite Conversation ii. 183 Why, Fire and Water are good Servants, but they are very bad Masters. 1808 J. ADAMS Works (1850-6) VI. 533 Like fire, they [i.e. the aristocracy] are good servants, but all-consuming masters. 1948 H. BESTON Northern Farm xxxvi. ‘Fire is a good servant but a bad master.’ So runs the proverb. 1973 J. CAIRD Murder Remote XX. Is not whisky the wonderful thing? But like fire, like fire—a good servant but a bad master. “ways and means
  

The same FIRE that melts the butter hardens the egg
People react in different ways to the same experience. Earlier in other variants; cf. 1623 BACON History of Life and Death (online ed.) In one and the same fire, clay grows hard and wax melts.

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  1952 J. F. BENDER Make Your Business Letters Make Friends 220 An approach that works in one instance may kill a sale in another. Remember the fire that hardens the egg softens the butter. 1995 D. T. LYKKEN Antisocial Personalities 81 The first day in school or a first roller-coaster ride will be a pleasurable excitement for some children.. but a terrifying and destructive experience for other children;.. the same fire that melts the butter hardens the egg. 2000 D. DE ARMAS WILSON Cervantes, Novel, and New World 131 The same fire that melts the butter hardens the egg. The same books that craze Don Quixote lead Dorotea.. out of a wilderness of seductions and betrayal. ■ experience
  

fire see also a BURNT child dreads the fire; DIRTY water will quench fire; FIGHT fire with fire; you should KNOW a man seven years before you stir his fire; if you PLAY with fire you get burnt; no SMOKE without fire; THREE removals are as bad as a fire.