(phrases and proverbs).
At swords' point.
In deadly hostility, ready to fight each other with swords. Poke
not fire with a sword. This was a precept of Pythagoras, meaning
add not fuel to fire, or do not irritate an angry man by sharp words
which will only increase his rage. (See Iamblichus Protreptics, symbol ix.)
To put to the sword.
Your tongue is a double-edged sword.
You first say one thing and then the contrary; your argument cuts
both ways. The allusion is to the double-edged sword out of the mouth
of the Son of Man- one edge to condemn, and the other to save. (Rev.
Yours is a Delphic sword- it cuts both ways.
Erasmus says a Delphic sword is that which accommodates itself to
the pro or con. of a subject. The reference is to the
double meanings of the Delphic oracles, called in Greek Delphike
Sword and Cloak Plays
So Calderon called topical or modern comedies, because the
actors wore cloaks and swords (worn by gentlemen of the period) instead
of heraldic, antique, or dramatico-historic dresses, worn in tragedy
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894