気き違ちがいに刃は物もの

Meanings

incredible danger; giving a sword to a madman

sensitive

Proverb meaning that giving a dangerous tool to an unstable person invites disaster. Literally 'a sword to a madman'. The term 気違い is now considered discriminatory, so the expression is sensitive and often avoided in modern usage.

彼かれにそんな権けん限げんを与あたえるのは、気き違ちがいに刃は物ものを渡わたすようなものだ。
Giving him that kind of authority is like handing a sword to a madman.
この状じょう況きょうで彼かの女じょを一人ひとりで行いかせるなんて、気き違ちがいに刃は物ものだよ。
Letting her go alone in this situation is incredibly dangerous.

Kanji

気spirit, mind, air
違difference, differ
刃blade, sword, edge
物thing, object, matter
狂lunatic, insane, crazy

Related words

火ひに油あぶらを注そそぐ
Both describe making a bad situation worse, but 気違いに刃物 specifically emphasizes giving a dangerous tool to an unstable person, while 火に油を注ぐ is about adding fuel to any kind of conflict or problem.

Built from

きちがい+刃は物もの

Written forms

気き違ちがいに刃は物もの
Standard kanji spelling for the proverb. Note: 気違い is now considered a discriminatory term; the expression is often avoided or replaced.
きちがいに刃は物もの
Kana spelling, sometimes used to soften the impact of the kanji form.
気狂きちがいに刃物はもの
Variant kanji spelling using 狂い instead of 違い; less common.

Etymology

A traditional Japanese proverb. The exact origin is uncertain, but it likely arose from the obvious danger of arming someone who is mentally unstable. The phrase uses the now-discriminatory term 気違い (madman), which has led to its declining use.