Narrated Abu Hurairah:
The Messenger of Allah ﷺ passed a man who was selling grain. He asked him: How are you selling? He informed him. Revelation them came down to him saying: "Put your hand into it." So he put his hand into it, and felt that it was damp. The Messenger of Allah ﷺ then said: "He who deceives has nothing to do with us."

حَدَّثَنَا أَحْمَدُ بْنُ مُحَمَّدِ بْنِ حَنْبَلٍ، حَدَّثَنَا سُفْيَانُ بْنُ عُيَيْنَةَ، عَنِ الْعَلاَءِ، عَنْ أَبِيهِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ ﷺ مَرَّ بِرَجُلٍ يَبِيعُ طَعَامًا فَسَأَلَهُ " كَيْفَ تَبِيعُ " . فَأَخْبَرَهُ فَأُوحِيَ إِلَيْهِ أَنْ أَدْخِلْ يَدَكَ فِيهِ فَأَدْخَلَ يَدَهُ فِيهِ فَإِذَا هُوَ مَبْلُولٌ فَقَالَ رَسُولُ اللَّهِ ﷺ " لَيْسَ مِنَّا مَنْ غَشَّ " .