Sahih al-Bukhari 1770
Narrated Ibn ' `Abbas:
Dhul-Majaz and `Ukaz were the markets of the people during the Pre-Islamic period of ignorance. 
When the people embraced Islam, they disliked to do bargaining there till the following Holy Verses 
were revealed:-- There is no harm for you If you seek of the bounty Of your Lord (during Hajj by 
trading, etc.) (2.198)
حَدَّثَنَا عُثْمَانُ بْنُ الْهَيْثَمِ، أَخْبَرَنَا ابْنُ جُرَيْجٍ، قَالَ عَمْرُو بْنُ دِينَارٍ قَالَ ابْنُ عَبَّاسٍ ـ رضى الله عنهما ـ كَانَ ذُو الْمَجَازِ وَعُكَاظٌ مَتْجَرَ النَّاسِ فِي الْجَاهِلِيَّةِ، فَلَمَّا جَاءَ الإِسْلاَمُ كَأَنَّهُمْ كَرِهُوا ذَلِكَ حَتَّى نَزَلَتْ ‏{‏لَيْسَ عَلَيْكُمْ جُنَاحٌ أَنْ تَبْتَغُوا فَضْلاً مِنْ رَبِّكُمْ‏}‏ فِي مَوَاسِمِ الْحَجِّ‏.‏