ENGLISH
REFERENCE

a two-edged sword

idiom
Meaning

Something that has both beneficial and harmful consequences.


Origin

The image runs through scripture. Hebrews 4:12 describes the word of God as living and active, sharper than any two-edged sword, and Proverbs 5:4 warns that the end of a seductive path is sharp as a two-edged sword — cutting in more than one direction.

A blade honed on both edges cuts on the forward stroke and the backstroke alike, making it more effective but also more dangerous to the person wielding it, and both scriptural uses trade on that double capacity to help and to harm.

In English a two-edged sword — often a double-edged sword — is anything whose strength is also its liability, a course of action or quality that works in your favour and against you at the same time.

Examples
SIMPLE

Fame is a two-edged sword.

CONTEXTUAL

The new technology is a two-edged sword, saving hours of work while quietly putting people out of jobs.

COMPLEX

Her bluntness was a two-edged sword: it won her the trust of clients who were tired of being flattered, and just as reliably it made enemies of colleagues who would have preferred a gentler kind of honesty.

Wisdom & Poetryconnected storiesSee all Biblical origin →

Job, Psalms, Proverbs and Ecclesiastes on how to live.

  1. 01

    nothing new under the sun (idiom)

    Human affairs endlessly repeat; what seems novel has all happened before.

  2. 02

    the patience of Job (idiom)

    Extraordinary endurance and calm in the face of prolonged suffering.

  3. 03

    by the skin of your teeth (idiom)

    Just barely

  4. 04

    pride comes before a fall (idiom)

    Arrogance and overconfidence tend to precede a downfall.

  5. 05

    a fly in the ointment (idiom)

    A small flaw or problem that spoils something otherwise good.

  6. 06

    my cup runneth over (idiom)

    A feeling of having blessings or good fortune in overwhelming abundance.

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