He nailed himself to his own petard

A podcaster was alleging that a possible 2024 candidate had already ruined his chances of getting into the race by making certain statements, and that “he nailed himself to his own petard”. This appears to be a mashup of “hoisted by (one’s) own petard” (to be injured or defeated by one’s own actions) and “nailed to a cross” (severely punished).

Interestingly, “petards” were metal balls filled with gunpowder which were used to blow up walls and gates. The gunpowder was lit by a slow-burning fuse, but there was always a danger that the device would explode too soon and “hoist” the person lighting it, that is, blow them up in the air. The phrase is from Shakespeare’s Hamlet: ‘For ’tis the sport to have the enginer Hoist with his own petard

A big thank you to Verbatim for hearing this one and sending it in.