Who are the chosen few? Where are the elysian fields? What is a Parthian shot? 

Whether your knowledge of classical and biblical allusions is colossal or has fallen by the wayside, the English language is full of such expressions, allusions that have become shorthand for particular qualities or situations.

The Facts on File Dictionary of Classical and Biblical Allusions
Contains alphabetically arranged entries that explain the meaning and origins of approximately two thousand allusions found in the Bible, as well as in Greek, Roman, Norse, and other mythologies, and includes examples of usage and cross-references.