Like soap opera, this phrase is one of those little bits of language which seems quite bizarre when you really look at it. But like soap opera, most of us don’t really look at it like that, because we’re so used to it.
And also, I think, like soap opera, it just feels right. For me I think that was because it seems somewhat classical, ancient. Maybe it’s because it makes me unconsciously think of aspects of Ancient Greek myths, like the story of Prometheus stealing fire from the gods, and Zeus’ thunderbolts.
Despite its classical feel though, the phrase is actually relatively modern, and its origin can be traced to a very specific point.
In early 18th-century London, the actor-manager John Dennis invented a new machine for creating the sound of thunder during plays. In 1709 he used it for the first time in his own play, Appius and Virginia. The play wasn’t a success, and closed after a short run. It was replaced by a production of Macbeth, and Dennis went along to the opening night, where he was outraged to hear the sound of his own invention! He reportedly stood up and shouted, Damn them! They will not let my play run, but they steal my thunder! The phrase was subsequently commonly used among theatrical circles, and didn’t really enter widespread use until the early 20th century.
This event was prominently featured in Alexander Pope’s satirical poem, The Dunciad:
With Shakspeare’s nature, or with Jonson’s art,
Let others aim: ’tis yours to shake the soul
With thunder rumbling from the mustard bowl,
And given that Pope’s title is a deliberately ironic reference to Ancient Greek epics like the Iliad, I suppose I wasn’t completely wrong to sense that the phrase might be a classical allusion. Not that the great Mr. Pope and I were on the same page exactly, but we weren’t exactly thinking completely differently either!