[The Squatter of Amon Rûdh]

That's Farmer Giles' wife, Agatha, berating her husband at the beginning of Farmer Giles of Ham.

'Don't stand there arguing!' said she. 'If you believe the dog, then take his advice: be bold and quick!'

Good advice, but nevertheless a change of subject by someone who feels she's losing the argument. 'Don't stand there arguing with me' is definitely implied.