In the prohibition of fraud

Muḥammad b. al-Ṣalt > Abū ʿAqīl Yaḥyá b. al-Mutawakkil > al-Qāsim b. ʿUbaydullāh > Sālim > Ibn ʿUmar

The Messenger of Allah ﷺ passed by some food in the market of the city. He was amazed by its beauty, so the Messenger of Allah ﷺ put his hand in it and took out something that was not visible. He frowned at the food vendor and then said, "There should be no cheating among Muslims. Whoever deceives us is not one of us." – Weak Chain

حَدَّثَنَا مُحَمَّدُ بْنُ الصَّلْتِ حَدَّثَنَا أَبُو عَقِيلٍ يَحْيَى بْنُ الْمُتَوَكِّلِ قَالَ أَخْبَرَنِي الْقَاسِمُ بْنُ عُبَيْدِ اللَّهِ عَنْ سَالِمٍ عَنْ ابْنِ عُمَرَ

أَنَّ رَسُولَ اللَّهِ ﷺ مَرَّ بِطَعَامٍ بِسُوقِ الْمَدِينَةِ فَأَعْجَبَهُ حُسْنُهُ فَأَدْخَلَ رَسُولُ اللَّهِ ﷺ يَدَهُ فِي جَوْفِهِ فَأَخْرَجَ شَيْئًا لَيْسَ كَالظَّاهِرِ فَأَفَّفَ لِصَاحِبِ الطَّعَامِ ثُمَّ قَالَ «لَا غِشَّ بَيْنَ الْمُسْلِمِينَ مَنْ غَشَّنَا فَلَيْسَ مِنَّا» – إسناده ضعيف