حَدَّثَنَا الْعَبَّاسُ بْنُ عَبْدِ الْعَظِيمِ الْعَنْبَرِيُّ، حَدَّثَنَا عَبْدُ الرَّزَّاقِ، أَنْبَأَنَا مَعْمَرٌ، عَنِ ابْنِ طَاوُسٍ، عَنْ أَبِيهِ، عَنِ ابْنِ عَبَّاسٍ، قَالَ نَهَى رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ أَنْ يَبِيعَ حَاضِرٌ لِبَادٍ ‏.‏ قُلْتُ لاِبْنِ عَبَّاسٍ مَا قَوْلُهُ حَاضِرٌ لِبَادٍ قَالَ لاَ يَكُونُ لَهُ سِمْسَارًا ‏.‏

Ibn Tawus narrated from his father that Ibn 'Abbas said: "The Messenger of Allah (PBUH) forbade a city-dweller to sell for a Bedouin." (Sahih)I (Tawus) said to Ibn 'Abbas: "What is meant by the words: 'A city-dweller selling for a Bedouin?' He said: "He should not be a broker for him." Translation Not Available

Book Ref: Sunan Ibn Majah Book 12 Hadith 2177
Web Ref:  Sunan Ibn Majah Vol 3 Book 12 Hadith 2177