Sahih al-Bukhari 6852
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 Messenger (ﷺ) if they sold it at the very place where they had bought it, till they 
carried it to their dwelling places.
حَدَّثَنِي عَيَّاشُ بْنُ الْوَلِيدِ، حَدَّثَنَا عَبْدُ الأَعْلَى، حَدَّثَنَا مَعْمَرٌ، عَنِ الزُّهْرِيِّ، عَنْ سَالِمٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّهُمْ كَانُوا يُضْرَبُونَ عَلَى عَهْدِ رَسُولِ اللَّهِ صلى الله عليه وسلم إِذَا اشْتَرَوْا طَعَامًا جِزَافًا أَنْ يَبِيعُوهُ فِي مَكَانِهِمْ حَتَّى يُئْوُوهُ إِلَى رِحَالِهِمْ‏.‏