وَحَدَّثَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، وَعَبْدُ بْنُ حُمَيْدٍ، قَالاَ حَدَّثَنَا عَبْدُ الرَّزَّاقِ، أَخْبَرَنَا مَعْمَرٌ، عَنِ ابْنِ طَاوُسٍ، عَنْ أَبِيهِ، عَنِ ابْنِ عَبَّاسٍ، قَالَ نَهَى رَسُولُ اللَّهِ صلى الله عليه وسلم أَنْ تُتَلَقَّى الرُّكْبَانُ وَأَنْ يَبِيعَ حَاضِرٌ لِبَادٍ ‏.‏ قَالَ فَقُلْتُ لاِبْنِ عَبَّاسٍ مَا قَوْلُهُ حَاضِرٌ لِبَادٍ قَالَ لاَ يَكُنْ لَهُ سِمْسَارًا.

Ibn 'Abbas (Allah be pleased with them) reported Allah's Messenger (PBUH) as saying: The riders (carrying merchandise) should not be met in the way, and townsman should not sell for a man of the desert. The narrator reported. I said to Ibn 'Abbas: What do these words really imply-" The townsman for the man of the desert"? He said: That he should work as a broker on his behalf. Translation Not Available

Book Ref: Sahih Muslim Book 21 Hadith 3629
Web Ref:  Sahih Muslim Book 10 Hadith 1521