light a fire under

Idioms  

1. Also, build a fire under. Urge or goad to action, as in If we don't light a fire under that committee, they'll never do any work. This hyperbolic colloquialism uses light in the sense of “ignite,” a usage dating from the mid-1100s.

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Example Sentences

Things move at a glacial pace when Celtic enter the transfer realm but if this powder-puff performance doesn't light a fire under the backside of the hierarchy - major shareholder, Dermot Desmond, in other words - then nothing will.

From BBC

As his Treasury Secretary Scott Bessent openly admitted, these threats are designed to "light a fire" under such stalled talks.

From BBC

She’s always going to her for advice, and Hamby always seems to know when to nurture and when to light a fire under Burrell.

From Los Angeles Times

“I think it would light a fire under people to show that we can do some things that we didn’t think we could do,” said Alagona, who in 2016 founded the California Grizzly Research Network.

From Los Angeles Times

Wouldn’t that light a fire under you?

From Salon