For the sake of the country, I would walk through fire and water without hesitation.
Tips
usage
Almost always paired with a hard or dangerous task — pledges willingness to take it on. The literal sense is 'when faced with [it], will not decline'. Often follows phrases like 赴汤蹈火 'jump into water and fire' or 万死 'die ten thousand deaths'.
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Formal and a bit heroic. Common in speeches, oaths, period dramas, and pledges of loyalty. Sounds overdramatic in casual conversation.
