Punishment of Disbelievers at War with Allah and His Apostle

Bukhari :: Book 8 :: Volume 82 :: Hadith 835

Narrated 'Abdullah bin 'Umar:

Those people who used to buy foodstuff at random (without weighing or measuring it) were beaten in the lifetime of Allah's Apostle if they sold it at the very place where they had bought it, till they carried it to their dwelling places.