hoist with your own petard

hoist by/with (one's) own petard

To be injured, ruined, or defeated by one's own action, device, or plot that was intended to harm another; to have fallen victim to one's own trap or schemes. (Note: "hoist" in this instance is the simple past-tense of the archaic form of the verb, "hoise.") I tried to get my boss fired by planting drugs on him, but I was hoist by my own petard when the police caught me with them beforehand.

See also: hoist, own, petard

hoist with (or by) your own petard

have your plans to cause trouble for others backfire on you.

The phrase is from Shakespeare's Hamlet: ‘For 'tis the sport to have the enginer Hoist with his own petard’. In former times, a petard was a small bomb made of a metal or wooden box filled with explosive powder, while hoist here is the past participle of the dialect verb hoise , meaning ‘lift or remove’.

See also: hoist, own, petard