Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) narrates that the Prophet (peace and blessings be upon him) passed by the grain sellers and saw some fine grain. He (peace and blessings be upon him) put his hand into it, and beneath it there was poor-quality grain. He (peace and blessings be upon him) said: "Sell this separately and sell that separately. Whoever deceives us is not one of us."
Imam al-Tabarani (may Allah have mercy on him) said: "Only Abu Ma'shar narrated this hadith from Nafi'."
Hadith Referenceالمعجم الأوسط / باب الألف / 2490
Hadith Takhrij«أخرجه الدارمي فى «مسنده» برقم: 2583، وأحمد فى «مسنده» برقم: 5208، والبزار فى «مسنده» برقم: 5971»