Sahih Muslim , Book 4, Hadith 1880 (USC-MSA) ⓘ
Jabir b. Abdullah reported: While the Messenger of Allah was delivering (a sermon) on Friday, a caravan of merchandise came to Medina. The Companions of the Messenger of Allah rushed towards it till only twelve persons were left with him including Abu Bakr and 'Umar; and it was at this occasion that this verse was revealed." And when they see merchandise or sport, they break away to it."
وَحَدَّثَنَا إِسْمَاعِيلُ بْنُ سَالِمٍ، أَخْبَرَنَا هُشَيْمٌ، أَخْبَرَنَا حُصَيْنٌ، عَنْ أَبِي سُفْيَانَ، وَسَالِمِ، بْنِ أَبِي الْجَعْدِ عَنْ جَابِرِ بْنِ عَبْدِ اللَّهِ، قَالَ بَيْنَا النَّبِيُّ صلى الله عليه وسلم قَائِمٌ يَوْمَ الْجُمُعَةِ إِذْ قَدِمَتْ عِيرٌ إِلَى الْمَدِينَةِ فَابْتَدَرَهَا أَصْحَابُ رَسُولِ اللَّهِ صلى الله عليه وسلم حَتَّى لَمْ يَبْقَ مَعَهُ إِلاَّ اثْنَا عَشَرَ رَجُلاً فِيهِمْ أَبُو بَكْرٍ وَعُمَرُ - قَالَ - وَنَزَلَتْ هَذِهِ الآيَةُ { وَإِذَا رَأَوْا تِجَارَةً أَوْ لَهْوًا انْفَضُّوا إِلَيْهَا}
also referenced under: Book 7, Hadith 50 (In-Book) & Hadith 863 (Reference)