Sahih Bukhari

Narrated Tawus:Ibn `Abbas said, ""The Prophet (ﷺ) forbade the meeting of caravans (on the way) and ordained that no townsman is permitted to sell things on behalf of a bedouin."" I asked Ibn `Abbas, ""What is the meaning of his saying, 'No townsman is permitted to sell things on behalf of a bedouin.' "" He replied, ""He should not work as a broker for him