Sahih (Sahih al-Bukhari)
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.
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